Subtract 27/21 from 30/20, Solve 1 10/20

Subtract 27/21 from 30/20

1^st number: 1 10/20, 2^nd number: 1 6/21

30/20 - 27/21 is 3/14.

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,
30/20 = 30 × 21/20 × 21 = 630/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
27/21 = 27 × 20/21 × 20 = 540/420
Subtract the two like fractions:
630/420 - 540/420 = 630 - 540/420 = 90/420
After reducing the fraction, the answer is 3/14

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