#### Answer

The mean is really close to 35.9.

#### Work Step by Step

The mean can be counted by summing all the data and dividing it by the number of data. Also, at each age group we take the midrange of the group to calculate. The midranges: 20-29:24.5, 30-39:34.5, 40-49:44.5, 50-59:54.5, 60-69:64.5, 70-79:74.5, 80-89:84.5. The mean: $\frac{24.5\cdot27+24.5\cdot27+34.5\cdot34+44.5\cdot13+54.5\cdot2+64.5\cdot4+74.5\cdot1+84.5\cdot1}{82}=35.84$. The mean is really close to 35.9.