Question

By working 8 hours per day, Marley's team can complete a task in 15.5 days. Bill's team works on the same task at the same speed; however, Bill's team works 7 hours and 45 minutes per day. How many days does it take Bill's team to complete the task?

Answer 1

The ratio of numbers of days required is the reciprocal of the ratio of the number of hours worked per day. Think of examples with easier numbers: if you work on a project 4 hours a day, it will take you 2 times as long as if you work 8 hours a day.

ratio of hours worked per day: 7 3/4 to 8 = 31 to 32
ratio of number of days required: 32:31
number of days required by Bill's team: 15.5%2A%2832%2F31%29+=+%2831%2F2%29%2A%2832%2F31%29+=+32%2F2+=+16

Answer 2

It will take 16 days.
8 Hours x 15.5 days = 124 Hours

Using this logic, we know 60 minutes in an hour and 45/60= .75. So it is 7.75 Hours.
124/7.75= 16.

Hope this helps :)