Subtract 10/20 from 42/21, Solve 2 0/21

Subtract 10/20 from 42/21

1^st number: 2 0/21, 2^nd number: 10/20

42/21 - 10/20 is 3/2.

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,
10/20 = 10 × 21/20 × 21 = 210/420
Subtract the two like fractions:
840/420 - 210/420 = 840 - 210/420 = 630/420
After reducing the fraction, the answer is 3/2
In mixed form: 11/2

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