00:01
Okay, so we're dealing with another word problem where we have variables, and we're going to use variable substitution here.
00:10
So let's say we have two people who are doing a job, and so we have ben, who's represented by the letter b, and we have danny, who's represented by the letter d.
00:21
And ben is a bit slower than danny, and so ben takes twice as long as danny does.
00:29
And danny's time is represented by the letter d here.
00:34
So then ben, who's represented by b, is equal to 2d.
00:39
And then we're given some times that danny takes to finish the job.
00:46
So if danny takes, let's say, 30 seconds.
00:49
So if d is equal to 30 seconds, then we have that ben is equal to 2 times 30 seconds, which is equal to 60 seconds, which we also know is equal to one minute...