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# Solving unit rate problem

CCSS.Math:

Jayda takes 3 hours to deliver newspapers on her route. What is the rate per hour at which she delivers the newspapers? Created by Sal Khan and Monterey Institute for Technology and Education.

## Video transcript

Jayda takes 3 hours to deliver
189 newspapers on her paper route. What is the rate per
hour at which she delivers the newspaper? So this first sentence tells us
that she delivers, or she takes, 3 hours to deliver
189 newspapers. So you have 3 hours for
every 189 newspapers. That's what the first
sentence told us. But we want to figure out the
rate per hour, or the newspapers per hour, so we can
really just flip this rate right here. So if we were to just flip it,
we would have 189 newspapers for every 3 hours, which is
really the same information. We're just flipping what's in
the numerator and what's in the denominator. Now we want to write it in as
simple as possible form, and let's see if this top number
is divisible by 3. 1 plus 8 is 9, plus 9 is 18. So that is divisible by 3. So let's divide this numerator
and this denominator by 3 to simplify things. So if you divide 189 by 3. Let's do it over on the
side right here. 3 goes into 189. 3 goes and 18 six times. 6 times 3 is 18. Subtract. Bring down the 9. 18 minus 18 was nothing. 3 goes into 9 exactly
three times. 3 times 3 is 9, no remainder. So if you divide 189 by 3, you
get 63, and if you divide 3 by 3, you're going to get 1. You have to divide both the
numerator and the denominator by the same number. So now we have 63 newspapers
for every 1 hour. Or we could write this as 63
over 1 newspapers per hour. Or we could write this as 63,
because 63 over 1 is the same thing as 63 newspapers
per hour.