Question

A group of adult males has foot lengths whh a mean of 28.23 cm and a standard deviation of 1.47 on. Use the range rule of thumb for identifying significant values to identify the limits separating values that are significanty low or significantly high. Is the adult man foot length of 31.7 cm significanty low or significantly high? Explain.

Answer 1

According to the range rule of thumb, a significantly low foot length would be less than 25.29 cm and a significantly high foot length would be greater than 31.17 cm. The foot length of 31.7 cm is significantly high.

Step-by-step explanation:

The range rule of thumb is a rough estimate for identifying significant values in a normal distribution. According to this rule, a value is considered significantly low if it is less than the mean minus twice the standard deviation, and significantly high if it is greater than the mean plus twice the standard deviation.

In this case, the mean foot length for adult males is 28.23 cm and the standard deviation is 1.47 cm. Using the range rule of thumb, a significantly low foot length would be less than 28.23 - 2(1.47) = 25.29 cm, and a significantly high foot length would be greater than 28.23 + 2(1.47) = 31.17 cm.

Since the foot length of 31.7 cm is greater than 31.17 cm, it is significantly high.