Point a is at (-2,4) => (x1,y1)
Midpoint is (2.5, 3.5) => (a,b)
Point B is (x2, y2)
To find midpoint we use formula
a= 2.5, b= 3.5, x1= -2 and y1= 4
Plug in all the values and findout x2, y2
multiply 2 on both sides to remove fraction
(5 = -2+x2 , 7 = 4+ y2)
5 = -2+x2, so x2= 7
7 = 4+ y2, so y2= 3
The point B is ( 7, 3)
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.
Use the law of cosines:
c² = 8² + 11² - 2•8•11 cos(37°)
c² ≈ 44.4402
c ≈ 6.66634
