Subtract 18/7 from 21/36, Solve 21/36

Subtract 18/7 from 21/36

1^st number: 21/36, 2^nd number: 2 4/7

21/36 - 18/7 is -167/84.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 7 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 7 × 36 = 252,
18/7 = 18 × 36/7 × 36 = 648/252
Subtract the two like fractions:
147/252 - 648/252 = 147 - 648/252 = -501/252
After reducing the fraction, the answer is -167/84

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