Subtract 56/21 from 30/20, Solve 1 10/20

Subtract 56/21 from 30/20

1^st number: 1 10/20, 2^nd number: 2 14/21

30/20 - 56/21 is -7/6.

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,
56/21 = 56 × 20/21 × 20 = 1120/420
Subtract the two like fractions:
630/420 - 1120/420 = 630 - 1120/420 = -490/420
After reducing the fraction, the answer is -7/6

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