How to use tables of normal distribution Practice Test

Alex took a test in physics and scored a 35. The class average was 27 and the standard deviation was 5.

Noah took a chemistry test and scored an 82. The class average was 70 and the standard deviation was 8.

Show that Alex had the better performance by calculating -

1. Alex's standard normal percentile and

2. Noah's standard normal percentile

When

and

Find

.