Subtract 18/21 from 36/20, Solve 1 16/20

Subtract 18/21 from 36/20

1^st number: 1 16/20, 2^nd number: 18/21

36/20 - 18/21 is 33/35.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
36/20 = 36 × 21/20 × 21 = 756/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420
Subtract the two like fractions:
756/420 - 360/420 = 756 - 360/420 = 396/420
After reducing the fraction, the answer is 33/35

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