00:01
So in this problem, we have sharon going to her train station.
00:05
And sharon has two methods of going there.
00:07
First, she has her bike, which takes her 12 minutes, and she can walk, which takes her 40 minutes.
00:13
And the question is, how far away is the train station? now, let's start off by denoting the biking speed, her bike speed at x miles per hour.
00:24
Now, the problem says that her walking is seven less than her biking speed, which means her walking speed is x minus seven miles per hour since x is her biking speed and we can use these two expressions to solve for the distance so let's start off by saying that distance the distance that an object travels is equal to the speed of the object multiplied by the time it travels and so let's start off with the bike so the bike the speed of the bike is x miles per hour and we're going to multiply that by time which is 12 minutes but since it's in miles per hour we need that in terms of hours and so 12 minutes is going to be 12 divided by 60 hours and for distance we'll write it at d to make it a bit easier and so d is going to equal one -fifth x 12 divided by 60 is 1 5th now for purposes that'll become clear later we're going to put this equation in terms of x.
01:38
And so we multiply both sides by five to get rid of the one fifth, and we get x equals 5d.
01:44
And this is going to be for the bike.
01:47
Now let's work on walking.
01:51
So again, distance equals speed times time...