# math

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what is an eay way to add 1/5 1/2 and 1/7. I have to find a number that they all go into for a similar denominator right? but how do I do that without taking forever.

Multiply the denominators:

5 x 2 x 7 = ??

=)

As Writeacher has noted, the common denominator is 70 in this case. Convert each fraction to the equivalent value with 70 as the denominagtr, and add them.
1/5 = 14/70
1/2 = 35/70
1/7 = 10/70

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