82.3k views
13 votes
The scores on a mathematics exam have a mean of 70 and a stadard deviation of 7. Find the x-value that corresponds to the z-score -1.45.

User Sharona
by
6.0k points

1 Answer

11 votes

Answer:

59.85

Explanation:

The scores on a mathematics exam have a mean of 70 and a stadard deviation of 7. Find the x-value that corresponds to the z-score -1.45.

We solve the above question using z score formula

z = (x-μ)/σ, where

x is the raw score

μ is the population mean = 70

σ is the population standard deviation = 7

z = -1.45

Hence:

-1.45 = x - 70/7

Cross Multiply

-1.45 × 7 = x - 70

-10.15 = x - 70

x = -10.15 + 70

x = 59.85

User JRunner
by
5.6k points