Subtract 25/21 from 21/36, Solve 21/36

Subtract 25/21 from 21/36

1^st number: 21/36, 2^nd number: 1 4/21

21/36 - 25/21 is -17/28.

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

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252
Likewise, for the 2nd fraction, since 21 × 12 = 252,
25/21 = 25 × 12/21 × 12 = 300/252
Subtract the two like fractions:
147/252 - 300/252 = 147 - 300/252 = -153/252
After reducing the fraction, the answer is -17/28

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