Subtract 8/20 from 27/21, Solve 1 6/21

Subtract 8/20 from 27/21

1^st number: 1 6/21, 2^nd number: 8/20

27/21 - 8/20 is 31/35.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
27/21 = 27 × 20/21 × 20 = 540/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
8/20 = 8 × 21/20 × 21 = 168/420
Subtract the two like fractions:
540/420 - 168/420 = 540 - 168/420 = 372/420
After reducing the fraction, the answer is 31/35

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