Math CentralQuandaries & Queries



I am struggling to come up with a formula for this word problem:

If Mark takes 3 hours to paint a picture and it takes Henry three times as long to paint the same picture, then:

How many pictures can each paint in 10 hours?

How many pictures can they paint together in 10 hours?

Also any helpful hints as to how to approach problems such as this would be appreciated.

Thanks so much,


Mark can paint a picture in 3 hours so it takes Henry 3 ×3 = 9 hours to paint a picture.

The approach to this problem is to think in terms of the rates at which they work. Mark can paint a picture in 3 hours so he paints at the rate of 1/3 of a picture per hour. So, how many pictures does he paint in 10 hours?

Apply this technique to Henry also.


About Math Central


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.
Quandaries & Queries page Home page University of Regina PIMS