Subject: Dividing Fractions

Name: Paula
Who is asking: Student
Level: Middle

Why do you have to change the division sign to a multiplication sign and invert the fraction that follows the division sign in order to get the answer to a division problem when you're working with fractions?

Hi Paula,

One technique that may help you understand is to think in terms of money. For example the question

How many 5 dollar bills are there in 200 dollars? has the answer 200/5 = 40.

In a similar way the question

How many quarters are there in 7 dollars? has the answer

Or, if you have a dollar and a half (3/2 dollars) and you want to know how many nickles there are in your dollar and a half then, since a nickle is one-twentieth of a dollar, the answer is

If you want a more algebraic answer you can find one in Invert and multiply the answer to a similar question we received some time ago.

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