Answer:
.13%
68.26%
2.28%
47.72%
49.87%
34.13%
Step-by-step explanation:
1.) standardize by subtracting the mean and dividng by the standard deviation
(625-1000)/125= -3
go to a ztable to get .0013 or (1-.9987)
this is equal to .13%
2.)
875<x<1125
standardize both seperately and subtract them
(875-1000)/125= -1 whose probability is .1587 (or 1-.8413)
(1125-1000)/125= 1 whose probability is .8413
.8413-.1587= 68.26%
3.)
Find the probability that someone paid less than 1250 and take its compliment
(1250-1000)/125= 2 which has a probability of .9772
take its compliment (1-.9772)= .0228= 2.28%
4.)
Same process as question 2
(750-1000)/125= -2 which has a probability of (1-.9772) = .0228
(1000-1000)/125= 0 which has a probability of .5
.5-.0228= .4772= 47.72%
5.) same deal as the previous question
(625-1000)/125= -3 which has a probability of (1-.9987)= .0013
(1000-1000)/125= 0 which has a probability of .5
.5-.0013= .4987= 49.87%
6.)same deal the previous question
(875-1000)/125= -1 which has a probability of (1-.8413)=.1587
(1000-1000)/125= 0 which has a probability of .5
.5-.1587= .3413= 34.13%
