Data was collected for 300 fish from the North Atlantic. The length of the fish (in mm) is summarized in the frequency distribution table below.
| Lengths (mm) | Frequency |
|---|---|
| 120 - 124 | 1 |
| 125 - 129 | 16 |
| 130 - 134 | 71 |
| 135 - 139 | 108 |
| 140 - 144 | 1 |
| 145 - 149 | 18 |
| 150 - 154 | 3 |
(a) What is the class width?
class width =
(b) What is the class midpoint for the third class?
class midpoint =