The table shows information about the ages of 90 employees in a factory.
Frequency
10
Age (a years)
15 < a < 25
25 < a < 35
35 < a < 45
45 < a < 55
55 < a < 65
29
18
26
7
Calculate an estimate for the mean age.

Suppose that prices of a gallon of milk at various stores in one town have a mean of $3.71 with a standard deviation of $0.10. using chebyshev's theorem, what is the minimum percentage of stores that sell a gallon of milk for between $3.41 and $4.01? round your answer to one decimal place.