Ratio Question

Question

All the members of a construction crew work at the same pace. Six of them working together are able to pour foundation in 22 hours. How many hours would this job take if the number of workers decreased 2 times?

Answer 1

Let's pause and think about an important mathematical phrase here. What does "decreased two times" mean? Don't confuse this with "decreased by two" which would mean there are 6-2 =4 workers left.

If the number of workers decreased two times, the number of workers left would be 6 - (6 * 1/2) = 6-3= 3 workers.

Now this is a ratio problem:

6 workers /22 hrs  = 3 / x

x = 22 * 3 / 6 = 11 hours

Answer: It would take the remaining workers 11 hours.