Answer:
area=basexheight
area=4.1x5.7
area=23.3
HELP SOMEONE EXPLAIN THIS PLEASE
Answer:
Entrance fee for children: $1.92
Entrance fee for adults: $3.92
Step-by-step explanation:
Total expenses for this year: $214.00
The child fee will be: $x
and the adult fee will be $(x+2)
Last year the number of children was 44
and the number of adults was 33
this year also has the same number of children and adults.
which means the entrance fee total for children will be $44x and for adults will be $33(x+2).
44x + 33(x+2) = 214
--> 44x + 33x + 66 = 214
--> 77x = 214 - 66 = 148
--> x = 148/77 = 1.92
So children's price is $1.92 and adults price is $1.92 + 2
hence:
Entrance fee for children: $1.92
Entrance fee for adults: $3.92
6. Determine the system of equations based on the following relationships and then solve
for the two integers.
a. Fourteen more than twice the first integer gives the second integer
b. The second integer increased by one is the square of the first integer
Answer: (-3,8) and (5,24)
The two pairs of integers that satisfy the given conditions are (-3, 8) and (5, 24).
To solve the system of equations, let's assign variables to the two integers. Let the first integer be represented by 'x' and the second integer by 'y'.
According to the given information:
a. Fourteen more than twice the first integer gives the second integer:
This can be expressed as: 2x + 14 = y
b. The second integer increased by one is the square of the first integer:
This can be expressed as: y + 1 = x^2
Now, we have a system of equations:
1) 2x + 14 = y
2) y + 1 = x^2
To solve this system, we can substitute the value of 'y' from equation 1) into equation 2):
2x + 14 + 1 = x^2
2x + 15 = x^2
Rearranging the equation, we have:
\(x^2 - 2x - 15 = 0\)
Factoring the quadratic equation, we get:
(x - 5)(x + 3) = 0
Setting each factor equal to zero:
x - 5 = 0 --> x = 5
x + 3 = 0 --> x = -3
Substituting the values of 'x' back into equation 1), we can find the corresponding values of 'y':
For x = 5:
2(5) + 14 = y
10 + 14 = y
y = 24
For x = -3:
2(-3) + 14 = y
-6 + 14 = y
y = 8
Therefore, the two pairs of integers that satisfy the given conditions are (-3, 8) and (5, 24).
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A=2 b=2 c=1 Find the value of 2abcosC
Answer:
\(2abCosC = 1\)
Step-by-step explanation:
The cosine rule is
=> \(a^2= b^2+c^2-2abCosC\)
For 2abCosC, it becomes
=> \(2abCosC = b^2+c^2-a^2\)
=> \(2abCosC = (2)^2+(1)^2-(2)^2\)
=> \(2abCosC = 1\)
A pet store has c tanks of fish. Each tank has 25 fish. Using c , write an expression for the total number of fish in the store.
Answer:
25c
Step-by-step explanation:
For example , if there are 3 tanks (or n is 3), the total number of fish would be 25* 3 = 75 fish.
A weather forecaster predicts that the May rainfall in a local area will be between 2 and 8 inches but has no idea where within the interval the amount will be. Let x be the amount of May rainfall in the local area, and assume that x is uniformly distributed over the interval 2 to 8 inches.
(a) Calculate the expected May rainfall. (Round your answer to 1 decimal place.) μx
(b) What is the probability that the observed May rainfall will fall within two standard deviations of the mean?
Within one standard deviation of the mean? (Round all intermediate and final answers to 4 decimal places.)
Probability of May rainfall will fall within two SD Probability of May rainfall will fall within one SD
a) The expected May rainfall is 5.0 inches.
b) The probability of May rainfall falling within one standard deviation of the mean is 0.6827, and within two standard deviations is 0.9545.
(a) To calculate the expected May rainfall, we need to find the mean (μx) of the uniform distribution. The mean of a uniform distribution can be found using the formula:
μx = (a + b) / 2
where a and b are the lower and upper limits of the distribution, respectively. In this case, a = 2 and b = 8. So,
μx = (2 + 8) / 2
μx = 10 / 2
μx = 5
(b) To find the probability that the observed May rainfall will fall within one and two standard deviations of the mean, we first need to calculate the standard deviation (σx) of the uniform distribution. The formula for the standard deviation of a uniform distribution is:
\(σx = √((b - a)^2 / 12)\)
Using the values of a and b from before, we have:
\(σx = √((8 - 2)^2 / 12)\)
σx = √(36 / 12)
σx = √3
For a uniform distribution, the probabilities of falling within one and two standard deviations of the mean are as follows:
- Within one standard deviation (±1σx): 68.27% or 0.6827
- Within two standard deviations (±2σx): 95.45% or 0.9545
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Sarah spent 30 minutes practicing her spelling words. She spent 3 times as much time reading. How many minutes did Sarah spend reading?
Sarah spends reading 30 min + \(0.05 min^{2}\).
What is a mathematical expression?An expression or mathematical expression is a finite collection of symbols that is well-formed according to context-dependent norms. To assist identify the sequence of operations and other features of logical syntax, mathematical symbols can denote numbers (constants), variables, operations, functions, brackets, punctuation, and grouping.
However, in modern mathematics, and particularly in computer algebra, formulae are considered expressions that may be evaluated as true or false based on the values assigned to the variables in the expressions.
The problem is in a mathematical expression.
30 min+3s min did Sarah spend reading
Convert s to min
.30min+3s min× 1min/60s
Cancel the common units and simplify.
Cross-cancel units.
30 min + \(0.05 min^{2}\)
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1.32 Factory defective rate. A factory quality control manager decides to investigate the percentage of defective items produced each day. Within a given work week (Monday through Friday) the percentage of defective items produced was 2%, 1.4%, 4%, 3%, 2.2%. (a) Calculate the mean for these data. (b) Calculate the standard deviation for these data, showing each step in detail.
Answer:
a) the mean percentage of defective item produced is 2.52 %
b) the standard deviation of percentage of defective item produced is 1.01%
Step-by-step explanation:
Given that;
the percentage of defective items produced was 2%, 1.4%, 4%, 3%, 2.2%.
sample size n = 5
a) Calculate the mean for these data
mean percentage of defective item produced will be;
\(x^{bar}\) = ∑x / n
\(x^{bar}\) = ∑x / n = ( 2% + 1.4% + 4% + 3% + 2.2% ) / 5
\(x^{bar}\) = 12.6 / 5
\(x^{bar}\) = 2.52 %
Therefore, the mean percentage of defective item produced is 2.52 %
b) Calculate the standard deviation for these data
Formula for standard deviation is;
S = √( (∑(x-\(x^{bar}\) )²) / (n-1) )
so we make a table;
x ( x - \(x^{bar}\) )% ( x - \(x^{bar}\) )²%
2% -0.52 0.2704
1.4% -1.12 1.2544
4% 1.48 2.1904
3% 0.48 0.2304
2.2%. -0.32 0.1024
summation 4.048
so (∑(x-\(x^{bar}\) )² = 4.048%
so we substitute the value into our equation;
S = √( (∑(x-\(x^{bar}\) )²) / (n-1) )
S = √( (4.048%) / (5-1) )
S = √( 4.048% / 4 )
S = √( 1.0121
S = 1.00598 % ≈ 1.01%
Therefore, the standard deviation of percentage of defective item produced is 1.01%
Theprofit(indollars)earnedbysellingwappletreesisrepresentedby w2 − 4w + 14. The profit (in dollars) earned by selling w pear trees is
represented by 2w + 10. Write a polynomial that represents how much more profit is earned by selling w apple trees than w pear trees.
\(w^2 - 6w + 4\) is a polynomial that represents how much more profit is earned by selling w apple trees than w pear trees.
The profit earned by selling w pear trees is 2w + 10
To find the difference in profit, we need to subtract the profit earned by selling w pear trees from the profit earned by selling w apple trees:
\((w^2 - 4w + 14) - (2w + 10)\)
Simplifying the expression:
\(w^2 - 6w + 4\)
Therefore, the polynomial that represents how much more profit is earned by selling w apple trees than w pear trees is \(w^2 - 6w + 4\).
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The following is a list of student TGA scores from Unit 3:
73, 83, 72, 71, 65, 70, 76, 73, 83, 73
(a) What is the mean score? Show your work.
(b) What is the median score? Show your work.
Please help worth 10 points is this true that line n is perpendicular to line p? I think the answer is C, is this correct or not?
Answer: A
because slope are
WORTH 25 points
Find the area of the parallelogram with given points.
(7,4)
(3,0)
(-4,9)
(13,0)
more help pls im so dumb
Does this table represent a function? Why or why not?
O
X
2
3
3
4
5
y
1
4
3
2
5
A. Yes, because there are different y-values.
B. Yes, because every x-value corresponds to exactly one y-value.
C.
No, because the y-values are positive.
D. No, because one x-value corresponds to two different y-values.
SUBMIT
The given table does not represent a function. The correct answer is D. No, because one x-value corresponds to two different y-values.
To determine if the table represents a function, we need to check if every x-value corresponds to exactly one y-value. Let's analyze the given table:
x | y
-------
O | 1
X | 4
2 | 3
3 | 2
3 | 5
4 |
5 |
From the table, we can see that the x-values are not unique. Both the values 3 and 4 appear twice in the x-column, but they have different corresponding y-values.
This violates the definition of a function, which states that each input (x-value) should have only one output (y-value).
Therefore, the given table does not represent a function.
The correct answer is D. No, because one x-value corresponds to two different y-values.
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if A and B are events with P(A)=0.8, P(A OR B)=0.87, P(A AND B)=0.23, find P(B).
Answer:
P(A or B) = P(A) + P(B) - P(A and B)
0.87 = 0.8 + P(B) - 0.23
0.87 = P(B) + 0.57
P(B) + 0.57 = 0.87
P(B) + 0.57-0.57 = 0.87-0.57
P(B) = 0.3
Answer: 0.3
The value of P(B)= 0.3
What is probability?It is a branch of mathematics that deals with the occurrence of a random event.
Given:
P(A)=0.8, P(A OR B)=0.87, P(A AND B)=0.23,
Now, using
P(A or B) = P(A) + P(B) - P(A and B)
0.87 = 0.8 + P(B) - 0.23
0.87 = P(B) + 0.57
P(B) + 0.57 = 0.87
P(B) = 0.87-0.57
P(B) = 0.3
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3415 base 7 ×(-432base 7)
Ignore the negative sign, since that only affects the sign of the final product
3415₇ × 432₇
You can compute the product by considering the digit expansion, by which I mean first expanding each number as sums of powers of 7:
3415₇ = 3000₇ + 400₇ + 10₇ + 5₇
(It's the same thing as writing, for example, the decimal 3415 as 3000 + 400 + 10 + 5, just in a different base.)
Similarly,
432₇ = 400₇ + 30₇ + 2₇
Then apply the distributive property:
= (3000₇ + 400₇ + 10₇ + 5₇) × (400₇ + 30₇ + 2₇)
= 3000₇ × (400₇ + 30₇ + 2₇)
… + 400₇ × (400₇ + 30₇ + 2₇)
… + 10₇ × (400₇ + 30₇ + 2₇)
… + 5₇ × (400₇ + 30₇ + 2₇)
= {12}00000₇ + {9}0000₇ + 6000₇
… + {16}0000₇ + {12}000₇ + {8}00₇
… + 4000₇ + 300₇ + 20₇
… + {20}00₇ + {15}0₇ + {10}₇
where I use the curly braces to indicate products (written in base 10) of digits that exceed 6. Anything in these braces needs to be properly converted to base 7. For example,
{12}₇ = 7 + 5 = 15₇
So you would have
= 1500000₇ + 120000₇ + 6000₇
… + 220000₇ + 15000₇ + 1100₇
… + 4000₇ + 300₇ + 20₇
… + 2600₇ + 210₇ + 13₇
Add everything up:
• In the 7⁰ place,
3₇
• In the 7¹ place,
1₇ + 1₇ + 2₇ = 4₇
• In the 7² place,
2₇ + 6₇ + 3₇ + 1₇ = {12}₇ = 15₇
• Carry the 1 (underlined). In the 7³ place,
2₇ + 4₇ + 1₇ + 5₇ + 6₇ + 1₇ = {19}₇ = 25₇
• Carry the 2. In the 7⁴ place,
1₇ + 2₇ + 2₇ + 2₇ = {7}₇ = 10₇
• Carry the 1. In the 7⁵ place,
2₇ + 1₇ + 5₇ + 1₇ = {9}₇ = 12₇
• Carry the 1. In the 7⁶ place,
1₇ + 1₇ = 2₇
So, we end up with
3415₇ × 432₇ = 22045543₇
and thus
3415₇ × (-432₇) = -22045543₇
Graph a triangle ABC and perform a translation of (x + 4, y - 3) to create triangle A'B'C'.
1. Describe the transformation using words. Make sure you refer to the characteristics
and the coordinates.
2. Draw a line through points A and A' and through points B and B'. What do you
notice about the lines you drew? Do you think you would notice the same
characteristics if you drew another line through points C and C'? How do you know?
1. The translation was of 4 units right and 3 units down.
2. All the blue lines connecting the equivalent vertices will have a slope of -3/4.
What is the translation?
The translations of the triangle is given by the rule presented as follows:
(x,y) -> (x + 4, y - 3).
Hence the meaning of each of these translations is given as follows:
x -> x + 4 is a translation of four units right.y -> y - 3 is a translation of three units down.The coordinates of the original vertices are given as follows:
(0,0), (0,4), (3,0).
Then the coordinates of the translated vertices are given as follows:
(4,-3), (4,1), (7,-3).
For a linear function, the slope is given by the vertical change divided by the horizontal change.
From these translations, the changes are given as follows:
Vertical change of 3 units down, hence of -3.Horizontal change of 4 units right, hence of +4.Thus the slope of the linear function connecting the original vertices are given as follows:
m = -3/4.
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Determine the amplitude of function
The amplitudes of functions are a) 8 and b) 6.
Given are the functions we need to determine the amplitude of function,
a) y = 8 Sin (x/2) + 3
b) y = 6 Cos x + 2
So,
To determine the amplitude of a trigonometric function, you can follow these steps:
For a sine function of the form y = A×sin(Bx + C) + D:
The amplitude is equal to the absolute value of the coefficient A.
For a cosine function of the form y = A×cos(Bx + C) + D:
The amplitude is equal to the absolute value of the coefficient A.
Let's apply these steps to the given functions:
a) y = 8×sin(x/2) + 3
The coefficient of sin in this function is 8, so the amplitude is |8| = 8.
Therefore, the amplitude of function a) is 8.
b) y = 6×cos(x) + 2
The coefficient of cos in this function is 6, so the amplitude is |6| = 6.
Therefore, the amplitude of function b) is 6.
Hence the amplitudes of functions are a) 8 and b) 6.
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(i) Write the zeroes of the polynomial by using above graph.
(ii)Form a quadratic polynomial for above graph.
(iii)If a,1/a are the zeroes of polynomial 2x² -x +8k, then find the value of k.
please answer
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There is no real Value of k that will satisfy the equation 2x² - x + 8k = 0 if a and 1/a are the roots of the polynomial.
(i) Zeroes of the polynomial:
In the graph, we have two points where the curve intersects the x-axis: one is at (-1,0), and the other is at (2,0).The corresponding values of x are -1 and 2, and they are the zeros of the polynomial. Therefore, the zeros of the polynomial are -1 and 2.(ii) Forming the quadratic polynomial:
From the graph, we can observe that the curve intersects the y-axis at the point (0,5), implying that the constant term of the polynomial is 5.
We can use the formula to find the quadratic polynomial if we have two zeros and one constant term. Thus, the quadratic polynomial is given by:(x + 1)(x - 2) = x² - x - 2x + 2 = x² - 3x + 2. Therefore, the quadratic polynomial is x² - 3x + 2.(iii) Value of k if a, 1/a are the zeroes of the polynomial 2x² - x + 8k:
We know that a and 1/a are the zeroes of the polynomial 2x² - x + 8k. Therefore, we can find the sum and product of the roots and use them to determine the value of k.
The sum of the roots is a + 1/a, and their product is a(1/a) = 1. Using the sum and product of the roots, we can write: a + 1/a = 1/2 (1/2 is the coefficient of x)Substituting a with 1/a in the above equation, we get: 1/a + a = 1/2Multiplying both sides of the equation by 2a, we get: 2 + 2a² = a
Simplifying the equation, we get: 2a² - a + 2 = 0Multiplying both sides by 2,
we get: 4a² - 2a + 4 = 0Dividing both sides by 2, we get: 2a² - a + 2 = 0
Using the quadratic formula, we get: a = [1 ± √(1 - 4(2)(2))]/(2(2))
Simplifying, we get: a = [1 ± √(-31)]/4Since the discriminant of the quadratic formula is negative, the roots are imaginary. Therefore, there is no real value of k that will satisfy the equation 2x² - x + 8k = 0 if a and 1/a are the roots of the polynomial.
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Find the length of AB.6 inAB = [ ? Jin0x30°ВRound your answer to the nearest hundredth.Enter
The given diagram shows a circle with radius (R) 6 inches, and the central angle of arc AB as 30 degrees,
\(\begin{gathered} R=6 \\ \theta=30^{\circ} \end{gathered}\)Consider that the length (L) of a circular arc of radius R and central angle Θ, is given by the formula,
\(\begin{gathered} L=\frac{\theta}{360}\cdot2\pi R \\ L=\frac{30}{360}\cdot2\pi(6) \\ L=\pi \\ L=3.14 \end{gathered}\)The problems in the picture
Eric recycles bottles at the local recycling center to earn money for a new bike.Eric keeps track of how much he earned in this graph
$108.50
1 bottle collected= $1.50 + $2.00 + $2.50 = $6.00
2 bottles " = $5.00
3 bottles " = $5.50 + $6.00 = $11.50
4 bottles " = $7.00 + $8.00 = $15.00
5 bottles " = $6.00 + $9.00 + $10.00 = $25.00
6 bottles " = $2.00 + $8.00 + $11.00 + $13.00 = $34.00
7 bottles " = $12.00
Then you add up all the answers to get the final amount Eric earned.
$6.00 + $5.00 + $11.50 + $15.00 + $25.00 + $34.00 + $12.00 = $108.50.
in the figure, △ABC is similar to △DEF. what is m∠1
Answer:
C. 139°
Step-by-step explanation:
Given:
m<A = 62°
m<B = 77°
Required:
Find m<1
Solution:
Since ∆ABC is similar to ∆DEF, therefore:
<A ≅ <D, which means m<D = 62°
<B ≅ <E, which means m<E = 77°
<C ≅ <F
Therefore, based on exterior angle theorem:
m<1 = m<D + m<E
m<1 = 62° + 77° (substitution)
m<1 = 139°
Over which interval of the domain is function h decreasing?
The interval of the domain of the considered function for which the function is decreasing is none. The function is strictly increasing: Option D: The function is increasing only.
When do we say that a function is decreasing?Suppose that the function is y = f(x)
If for an interval I, when x increases meanwhile staying in the interval I, the function's output decreases (or can stay same), then we say that the function is decreasing in the interval I.
This interval I was of values that x can take for this function, which is the domain of the considered function, so we say:
y = f(x) is decreasing function in an interval I if:
\(f(x+\delta) \leq f(x) \: \forall x \in I : x+\delta \in I\)
If we have:
\(f(x+\delta) < f(x) \: \forall x \in I : x+\delta \in I\), then the function is called strictly decreasing in the interval I.
Similarly, there increasing( \(f(x+\delta) \geq f(x) \: \forall x \in I : x+\delta \in I\) ) and strictly increasing(\(f(x+\delta) > f(x) \: \forall x \in I : x+\delta \in I\) ) functions.
For this case, the function is:
\(h(x) = \left \{ {{2^x, x < 1} \atop \: \atop {\sqrt{x+3}, x \geq 1}} \right.\)
The function is differentiable in either side of 1.
Sign of rate of function at a point tells whether its increasing or decreasing.
For x < 1:\(h'(x)= 2^x ln(2)\)
We know that:
\(2^x > 0 \: \rm \forlall x \in \mathbb R\)
And \(ln(2) \approx 0.69 > 0\)
Thus, \(h'(x)= 2^x ln(2) > 0 \: \forall x \in \mathbb R\)
So, rate is positive, the function is strictly increasing for this case.
For x > 1:\(h'(x) = \dfrac{1}{2\sqrt{(x+3)}}\)
For all x > 1, \(\sqrt{x+3} > 0\), and so as h'(x)
So rate is positive and therefore strictly increasing for this case too.
For x = 1:\(h(1+\delta) - h(1)= \sqrt{1+\delta + 3} - \sqrt{1+3} = \sqrt{4+\delta} - \sqrt{4} > 0 \forall \delta > 0\)
So rate of the considered function is positive,so function is strictly increasing all over the domain.
Thus, the interval of the domain of the considered function for which the function is decreasing is none. The function is strictly increasing: Option D: The function is increasing only.
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What’s the measure of x for the for each figure?
Answer:
a)73
b)27
c)58
d)70
C
55
Solve for C.
90
C = [?]
Round your
to the nearest tenth.
final answer
50
Law of Cosines: c² = a² + b² - 2ab-cosC
Measure of Angle C
Answer:
29.4°
Step-by-step explanation:
The equation can be rearranged to give C directly.
C = arccos((a^2 +b^2 -c^2)/(2ab))
C = arccos((90^2 +55^2 -50^2)/(2·90·55))
C = arccos(8625/9900) ≈ 29.4002°
C ≈ 29.4°
The measure of angle C is approximately 29.46 degrees.
How to determine angle CTo find the measure of angle C (cos(C)) using the given values a = 55, b = 90, and c = 50, we can use the Cosine Rule formula:
cos(C) = (a² + b² - c²) / (2 * a * b)
Substitute the given values:
cos(C) = (55² + 90² - 50²) / (2 * 55 * 90)
Now, calculate the numerator:
cos(C) = (3025 + 8100 - 2500) / (2 * 55 * 90)
cos(C) = 8625 / 9900
Now, divide to get the final value of cos(C):
cos(C) ≈ 0.8707
To find the measure of angle C itself, we can take the inverse cosine (arccos) of this value:
C ≈ arccos(0.8707)
Using a calculator, you'll find:
C ≈ 29.46 degrees (rounded to two decimal places)
So, the measure of angle C is approximately 29.46 degrees.
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if Ps = 4x+8, PQ = 29, RS = 5x -3, and QR=29, then Ps=
Answer:
What is X?
Step-by-step explanation:
4 multiplied by X + 8 =Ps
Ross is buying hats for his baseball team. Each package contains 4 hats. Generate the set of ordered pairs for the ratio relationship between the number of hats y and the number of packages x for a total of 1, 2, 3, and 4 packages, Then graph the relationship on the coordinate plane and describe the pattern in the graph. Hats
Being timed so please be fast
Aeronautical researchers have developed three different processes to pack a parachute. They want to compare the different processes in terms of time to deploy and reliability. There are 1,200 objects that they can drop with a parachute from a plane. Using a table of random digits, the researchers will randomly place the 1,200 items into three equally sized treatment groups suitable for comparison.
How should the items be labeled to select the process groups using a table of random digits?
A 1–3
B 1–1200
C 0000–1200
D 0000–1199
Answer:
0000–1199
Step-by-step explanation:
Edge 2020/2021
a medical researcher wants to determine whether exercising can lower blood pressure. she recruits 100 people with high blood pressure to participate in the study. she assigns a random sample of 50 of them to pursue an exercise program that includes daily swimming and jogging. she assigns the other 50 to refrain from vigorous activity. she measures the blood pressure of each of the 100 individuals both before ad after the study. press space or enter to grab observational study a medical researcher wants to determine whether exercising can lower blood pressure. at a health fair he measures the blood pressure of 100 individuals and interviews them about their exercise habits. he divides the individuals into two categories: those whose typical level of exercise is low and those whose level of exercise is high. press space or enter to grab randomized experiment to determine the effectiveness of a new pain reliever a randomly chosen group of pain sufferers is assigned to take the new drug and another randomly chosen group is assigned to take a placebo. press space or enter to grab randomized experiment to assess the effectiveness of a new method for teaching arithmetic to elementary school children a simple random sample of 30 first graders was taught with the new method and another simple random sample of 30 first graders was taught with the currently use method. at the end of eight weeks the children were given a test to assess their knowledge. the press space or enter to grab observational study researchers examine the association between the fluoridation of water and the prevention of tooth decay by comparing the prevalence of tooth decay in countries that have fluoridated water with the prevalence in countries that do not.
The study described is a randomized experiment.
A randomized experiment is a typical experimental study design. It is a study design in which the researcher or investigator is in complete control of the research environment. For example, an investigator may wish to assess the effects of certain treatments on some experimental units.
The investigator decides the type of treatment, the type of experimental unit to use, and the allocation and assessment procedures of the treatments and effects, respectively, while in an observational study, the researcher or investigator is usually a passive observer as he only observes and analyses facts and events as they occur naturally.
In experimental studies, the researcher is in complete control of the exposure, and the result should therefore provide stronger evidence of an association or lack of association between exposure and a health problem than would an observational study.
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"Determine whether the study described below is a randomized experiment or an observational study.
A medical researcher wants to determine whether exercise can lower blood pressure. She recruits 100 people with high blood pressure to participate in the study. She assigns a random sample of 50 of them to pursue an exercise program that includes daily swimming and jogging. She assigns the other 50 to refrain from vigorous activity. She measures the blood pressure of each of the 100 individuals both before and after the study."--
John ran 1 of a mile in 8 minutes. If he continues running 2 at that speed, how long will it take him to run one mile? A) 4 minutes B) 8 minutes C) 12minutes D) 16 minutes
Answer:
d 16 minutes
Step-by-step explanation:
1 mile equals 8 minutes
2 miles equals 16 minutes