Subtract 21/42 from 56/36, Solve 1 20/36

Subtract 21/42 from 56/36

1^st number: 1 20/36, 2^nd number: 21/42

56/36 - 21/42 is 19/18.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 42 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 36 × 7 = 252,
56/36 = 56 × 7/36 × 7 = 392/252
Likewise, for the 2nd fraction, since 42 × 6 = 252,
21/42 = 21 × 6/42 × 6 = 126/252
Subtract the two like fractions:
392/252 - 126/252 = 392 - 126/252 = 266/252
After reducing the fraction, the answer is 19/18
In mixed form: 11/18

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