Answer:
Step-by-step explanation:
Given that the random variable X is normally distributed, with
mean = 50 and standard deviation = 7.
Then we have z= 
Using this and normal table we find that
a) 
b) When z=0.02
we get

c) 90th percentile z value =1.645
90th percentile of X 
Answer:
area = (1/2) · (p + q) · h
Step-by-step explanation:
Simplest way to do this:
number of books= 120
percentage represented by 120= 100%
increase current percent by 55%= 155%
: . 55% increase = original number of books * (155%)
= 120 * (155/100)
= 186
Answer:
Step-by-step explanation:
x y
−1 −2
2 3
3 1
6 −2