Question

Assume that the readings at freezing on a batch of thermometers are normally distributed with a mean of 0°C and a standard deviation of 1.00°C. A single thermometer is randomly selected and tested. Find P₄₅, the 45-percentile. This is the temperature reading separating the bottom 45% from the top 55%.

P₄₅ = °C

Answer 1

Since the thermometer reading is normally distributed hence it follows Z statistic for percentile value calculator. Hence, at 45 percentile the Z value is Z = -0.126, so by Z formula

The temperature reading separating the bottom 45% from the top 55%.

P₄₅ = -0.126 °C

Z value table