Question
Draw the frequency polygon using mid-ponts for the following data on time required to do a certain job.
| Time required (in hours) | 50-70 | 70-90 | 90-110 | 110-130 | 130-150 | 150-170 | 170-190 |
| No. of workers | 2 | 8 | 30 | 25 | 14 | 19 | 2 |
