Subtract 21/36 from 64/21, Solve 3 1/21

Subtract 21/36 from 64/21

1^st number: 3 1/21, 2^nd number: 21/36

64/21 - 21/36 is 69/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 21 × 12 = 252,
64/21 = 64 × 12/21 × 12 = 768/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252
Subtract the two like fractions:
768/252 - 147/252 = 768 - 147/252 = 621/252
After reducing the fraction, the answer is 69/28
In mixed form: 213/28

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