What is the mean of the following distribution?
| Marks | 19 | 31 | 54 | 69 | 95 |
| No. of Students | 22 | 35 | 64 | 34 | 57 |
Due to decrease in manpower, the production in a factory decreases by 10%. By what percentage should the working hours be increased to restore the original production?
16 \( \frac{2}{3} \) %
8 \( \frac{1}{3} \) %
11 \( \frac{1}{9} \) %
10%