Explanation:
Let's assume that it takes Chuck x minutes to fill the bucket alone.
We know that Bobby can fill the bucket alone in 40 minutes, which means that in one minute, Bobby can fill 1/40 of the bucket.
We also know that Bobby and Chuck working together can fill the bucket in 15 minutes, which means that in one minute, they can fill 1/15 of the bucket together.
To find out how much of the bucket Chuck can fill in one minute, we can subtract Bobby's contribution from the combined contribution of both of them:
1/15 - 1/40 = 8/120 - 3/120 = 5/120
So we know that in one minute, Chuck can fill 5/120 of the bucket.
To find out how long it would take Chuck to fill the bucket alone, we can set up a proportion:
5/120 = 1/x
Cross-multiplying, we get:
5x = 120
x = 24
Therefore, it would take Chuck 24 minutes to fill the bucket alone.