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

Subtract 20/21 from 30/20

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

30/20 - 20/21 is 23/42.

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,
20/21 = 20 × 20/21 × 20 = 400/420
Subtract the two like fractions:
630/420 - 400/420 = 630 - 400/420 = 230/420
After reducing the fraction, the answer is 23/42

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