Question 970659
12 men can finish half a job in 35 minutes;
Find how many man-minutes to complete half the job
12 * 35 = 420 man minutes, to do half the job
:
 how many more men are needed if the remaining job should be completed in 15 minutes?
Let m = no. of men to accomplish this
15m = 420
m = 420/15
m = 28 men required