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=26
Step-by-step explanation:
first rewrite the problem since u know that G(x)=-48
-48=-3/2x-9
second you want to add the 9 to -48 which gives u -39
-39=-3/2x
third you want to times the reciprocal so it would be
-2/3 times -39/1
u can cross out the negatives and turn them into a positive
fourth you can cross cancel 3 and 39 which now the problem looks like this
2/1 times 13/1
which you would times 2 and 13 which your answer would be
26
Confusing to me, sorry i cant help. I am not good with graphs.
Answer:
أيتها القبيحة أيتها العاهرة الغبية تذهب إلى المدرسة
Step-by-step explanation: أيتها القبيحة أيتها العاهرة الغبية تذهب إلى المدرسة
