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
Answer:
X = 59
Step-by-step explanation:
2 × 59 = 118
18 + 18 + 59 + 59 = 154
Equation = 2x + 7
Y-intercept = (0,7)
Answer:
B. 
Step-by-step explanation:
We are asked to find the body surface area of a person whose height is 150 cm and who weighs 80 kg.

Substitute the values:





Therefore, the body surface area of the person would be 1.83 square meters.
Answer:
341.125
Step-by-step explanation:
8187/24
341.125