00:01
For this problem here, we're going to be using the formula 1 over a plus 1 over b equals 1 over t.
00:07
Where a represents the work done for each cook, in this case, be the first one here, which is done in 6 hours, and then we have a second cook that's going to be there, and they do it in 7 hours.
00:19
But now we're going to be getting a third cook.
00:21
So we're going to throw on a third fraction here of 1 over c.
00:24
So a, b, and c represents the individual times, and t represents the time together.
00:28
So for the first cook, it's 1 over 6.
00:32
Plus, now we have a second cook that was included, and they do it in 7 hours, so they're going to be 1 over 7.
00:38
And the third cook is unknown, so we leave that as 1 over c.
00:42
But we are told that one that joined, then they prepared all the pies in 2 hours.
00:47
So this would be equal to 1 over 2.
00:50
So from here, we're going to go ahead and get the common denominator.
00:53
So between 6 and 7 and c and 2, the common denominator is essentially 42, 3.
00:59
So we're going to distribute through with the 42c...