Question

192) The monthly amounts spent for food by families of four receiving food stamps approximates a symmetrical, normal distribution. The sample mean is $150 and the standard deviation is $20. Using the Empirical ruleabout 95% of the monthly food expenditures are between what two amounts?

Answer 1

Let X dollars be the the monthly food expenditure of a randomly selected family of four. X is normally distributed wit mean $150 and standard deviation $20

The empirical rule states that

• About 95% of all the values in a normally distributed population lie with in 2 standard deviation from the mean.

Here,

2 standard deviations below the mean is

2 standard deviations above the mean is

ans: About 95% of the monthly food expenditures are between $110 and $190