Subtract 75/20 from 6/21, Solve 6/21

Subtract 75/20 from 6/21

1^st number: 6/21, 2^nd number: 3 15/20

6/21 - 75/20 is -97/28.

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,
6/21 = 6 × 20/21 × 20 = 120/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
75/20 = 75 × 21/20 × 21 = 1575/420
Subtract the two like fractions:
120/420 - 1575/420 = 120 - 1575/420 = -1455/420
After reducing the fraction, the answer is -97/28

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