Answer:
1/2 hour per day.
Step-by-step explanation:
Using proportion:
200 men make the embankment 5 km long in 25 days
1 man .............................................5 km ...... in 25*200 days
1 man ...............................................2 km ....... in 2/5 * 25*200= 2000 days
At this rate 60 men will finish the work in 2,000 / 60 = 33 1/3 days.
If they make it in 32 days they will have to work 1 /1/3 days overtime which is 16 hours'
So they have to work an extra 1/2 hour per day.
