Depending on where you live and on the quality of the day care, costs of day care can range from $3000 to $15,000 a year (or $250 to $1250 a month) for one child, according to the Baby Center. Day care centers in large cities such as New York and San Francisco are notoriously expensive. Suppose that day care costs are normally distributed with a mean equal to $9000 and a standard deviation equal to $1800. Source: www.babycenter.com/
a. What percentage of day care centers cost between $7200 and $10,800?
b. What percentage of day care centers cost between $5400 and $12,600?
c. What percentage of day care centers cost between $3600 and $14,400?
d. Compare the results in a through c with the empirical rule. Explain the relationship.