The mass of a species of mouse commonly found in houses is normally distributed with a mean of 20.3 grams with a standard deviation of 0.15 grams.

Question

For parts (a) through (c), enter your responses as a decimal with 4 decimal places.

a) What is the probability that a randomly chosen mouse has a mass of less than 20.22 grams? 

b) What is the probability that a randomly chosen mouse has a mass of more than 20.38 grams? 

c) What proportion of mice have a mass between 20.24 and 20.4 grams? 

d) 25% of all mice have a mass of less than ___ grams.

Answer 1

Calculate z value for given mass. Find the area under the curve on z distribution. Pay attention to your lower and upper limit for z. You can use calculator or chart.