The following data gives the weights (in grams) of some marbles picked up randomly from 3 boxes. The data was presented in the tabular form as below :
| Weight (in g) | No. of marbles |
| 50-55 | 5 |
| 55-60 | 7 |
| 60-65 | 8 |
| 65-70 | 6 |
| 70-75 | 2 |
| 75-80 | 1 |
| 80-85 | 1 |
Based on the above information, answer the following questions:
Q.1. Class size of the given distribution is :
(a) 5 (b) 10 (c) 50 (d) 85
Q.2. Class mark of the 3rd class is :
(a) 60 (b) 65 (c) 125 (d) 62.5
Q.3. The number of marbles whose weight is more than or equal to 75 g is :
(a) 0 (b) 1 (c) 2 (d) 28
Q.4. The number of marbles whose weight is less than 70 g is :
(a) 26 (b) 28 (c) 4 (d) 2
Q.5. The class boundaries of the 7th class interval are :
(a) 80, 85 (b) 80.5, 85.5 (c) 79.5, 85.5 (d) 80, 85.5