Video Transcript
What value of speed in miles per hour is equal to a speed of one kilometer per hour?
Here we have a speed of one kilometer per hour. And we need to find the equivalent value in miles per hour, which means we want to end up with distance unit of miles and the time unit of hours. To answer this question, we’re going to take our initial speed of one kilometer per hour and we’re going to multiply it by a fraction. Now, the fraction needs to be equal to one so that we’re not changing the value. But it needs to convert the units from kilometers into miles. We’ll do this by having miles in the numerator and kilometers in the denominator so that these kilometers will cancel and we’ll be left with units of miles per hour.
To find the value that needs to go in here, we need to recall that one mile is approximately equal to 1.6 kilometers. And therefore, if we make our fraction one mile divided by 1.6 kilometers, then this fraction now meets our two conditions. It’s equal to one and our kilometers cancel, leaving us with units of miles per hour. So the value that goes in here is one times one divided by 1.6, or 0.625. And so one kilometer per hour is equal to 0.625 miles per hour.
