probability and statistics

Question

Assume that the readings at freezing on a batch of thermometers are Normally distributed with mean 0°C and standard deviation 1.00°C.

Find P₇₅, the 75-percentile of the distribution of temperature readings. This is the temperature reading separating the bottom 75% from the top 25%.

Answer 1

The 75th percentile corresponds to a z-score of of 0.67.

Since readings are N(0,1), the 75th percentile is 0.67 degrees C.