Answer: About 99.7% IQ scores falls within 43 and 157.
Step-by-step explanation:
According to the empirical rule , if a data follows normal distribution then about 99.7% of the population lies with in three standard deviations from mean.
Given: IQ test have a bell-shaped distribution with a mean of 100 and a standard deviation of 19.
Since , the graph of normal distribution is bell-shaped , it mean that IQ scores follow normal distribution.
Then, About 99.7% IQ scores falls within Mean ± 3 (Standard deviation).
i.e. About 99.7% IQ scores falls within 100± 3(19).
i.e. About 99.7% IQ scores falls within 100- 57 and 100+57.
i.e. About 99.7% IQ scores falls within 43 and 157.
Therefore , by empirical rule
About 99.7% IQ scores falls within 43 and 157.
9514 1404 393
Answer:
A. (4, 12)
Step-by-step explanation:
Adding the second equation to twice the first will eliminate y.
2(10x +2y) +(3x -4y) = 2(64) +(-36)
23x = 92 . . . . . . . . simplify
x = 4 . . . . . . . . . divide by 23
This value matches choice A: (4, 12).
Answer:
- 6
Step-by-step explanation:
The average rate of change of f(x) in the closed interval [ a, b ] is

Here [ a, b ] = [ 2, 6 ] , then
f(b) = f(6) = - 6² + 2(6) + 2 = - 36 + 12 + 2 = - 22
f(a) = f(2) = - 2² + 2(2) + 2 = - 4 + 4 + 2 = 2 , then
average rate of change =
=
= - 6