Subtract 6/20 from 42/21, Solve 2 0/21

Subtract 6/20 from 42/21

1^st number: 2 0/21, 2^nd number: 6/20

42/21 - 6/20 is 17/10.

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,
42/21 = 42 × 20/21 × 20 = 840/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
6/20 = 6 × 21/20 × 21 = 126/420
Subtract the two like fractions:
840/420 - 126/420 = 840 - 126/420 = 714/420
After reducing the fraction, the answer is 17/10
In mixed form: 17/10

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