Subtract 9/21 from 42/36, Solve 1 6/36

Subtract 9/21 from 42/36

1^st number: 1 6/36, 2^nd number: 9/21

42/36 - 9/21 is 31/42.

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,
42/36 = 42 × 7/36 × 7 = 294/252
Likewise, for the 2nd fraction, since 21 × 12 = 252,
9/21 = 9 × 12/21 × 12 = 108/252
Subtract the two like fractions:
294/252 - 108/252 = 294 - 108/252 = 186/252
After reducing the fraction, the answer is 31/42

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