First let’s find the
mean and standard deviation for both test and then we can calculate the
probability of getting that score in his respective test and compare.
First test
P(x < 56)
P(z < 56-47.80/16.38)
P(z<0.50) = 1 – 0.3085
= 0.6915 or 69 percentile
Second test
P(x < 74)
P(z < 74 – 73.45 /
8.37)
P(z<0.07) = 1 – 0.4721=
0.5279 or 53 percentile
The probability for this
normal distribution also means the percentile, so we can say that in the first
test she was in the 69 percentile while in the second test she was in the 53
percentile. Therefore, she did worse in the second test
