Answer:
Step-by-step explanation:
Given:
Waiting time = 5 hours.
We need to find the number of minutes for 5 hours.
Solution:
We know that 60 minutes for each hour, so one hour is equal to 60 minutes.
For one hour = 
For five hours = 
Therefore, you will have to wait 300 minutes in a line.
Answer:
Step-by-step explanation:
The easiest way to fill out the graph is to find the slope.
The slope is y = 2x + 1.
Insert the x values of the graph for x in the equation to find y.
y = 2(-6) + 1 = -12 + 1 = -11. (-6, -11).
y = 2(-2) + 1 = -4 + 1= -3. (-2, -3).
Then, for finding x, just insert y.
1 = 2x + 1. Subtract 1 from both sides to isolate x.
0 = 2x. x = 0. (0, 1).
y = 2(2) + 1 = 4 + 1 = 5. (2, 5)
3 = 2x + 1. Subtract 1 from both sides.
2 = 2x. x = 1. (1, 3).
The slope of this function is 2x. The y-intercept is 1. The x-intercept is -2.
Let's call our estimate x. It will be the average of n IQ scores. Our average won't usually exactly equal the mean 97. But if we repeated averages over different sets of tests, the mean of our estimate the average would be the same as the mean of a single test,
μ = 97
Variances add, so the standard deviations add in quadrature, like the Pythagorean Theorem in n dimensions. This means the standard deviation of the average x is
σ = 17/√n
We want to be 95% certain
97 - 5 ≤ x ≤ 97 + 5
By the 68-95-99.7 rule, 95% certain means within two standard deviations. That means we're 95% sure that
μ - 2σ ≤ x ≤ μ + 2σ
Comparing to what we want, that's means we have to solve
2σ = 5
2 (17/√n) = 5
√n = 2 (17/5)
n = (34/5)² = 46.24
We better round up.
Answer: We need a sample size of 47 to be 95% certain of being within 5 points of the mean
