Question

A group of adult males has foot lengths with a mean of 27.75 cm and a standard deviation of 1.13 cm. Use the range rule of thumb to identify the limits separating values that are significantly low or significantly high. Is the adult male foot length of 30.4 cm significantly low or significantly​ high? Explain.

Answer 1

Solution :

Given that ,

mean = = 27.75

standard deviation = = 1.13

Use the range rule of thumb

significantly low = - 2

significantly low = 27.75 - 2 * 1.13

significantly low = 25.49

significantly high = + 2

significantly high = 27.75 + 2 * 1.13

significantly high = 30.01

The adult male foot length of 30.4 cm is significantly​ high, because it is greater than 30.01 cm.