Solve Write a Mixed Numeral for the Answer $0 \mathrm{mph}$ To $60 \mathrm{mph}$

Solve. Write a mixed numeral for the answer.
-A road acceleration test measures the time in seconds required to go from $0 \mathrm{mph}$ to $60 \mathrm{mph}$ . The results for five cars were as follows: $6 \frac{3}{10} \mathrm{sec}, 7 \frac{2}{5} \mathrm{sec}, 8 \frac{1}{10} \mathrm{sec}, 6 \frac{4}{5} \mathrm{sec}$ , and $7 \frac{1}{2} \mathrm{sec}$ . What was the average time?

A) $7 \frac{27}{100} \mathrm{sec}$
B) $7 \frac{31}{50} \mathrm{sec}$
C) $7 \frac{1}{10} \mathrm{sec}$
D) $7 \frac{11}{50} \mathrm{sec}$