Answer:
Between 21 years and 75 years
Explanation:
Given that a real estate company is interested in the ages of home buyers. They examined the ages of thousands of home buyers and found that the mean age was 48 years old, with a standard deviation of 9 years.
X the ages of home buyers is N(48, 9)
a)

Hence using Cheby chev inequality

b)


c) Using normal distribution we have

d) z value is 2.97
Hence x lies between

Between 21 years and 75 years