Subtract 6/20 from 63/42, Solve 1 21/42

Subtract 6/20 from 63/42

1^st number: 1 21/42, 2^nd number: 6/20

63/42 - 6/20 is 6/5.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
63/42 = 63 × 10/42 × 10 = 630/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
6/20 = 6 × 21/20 × 21 = 126/420
Subtract the two like fractions:
630/420 - 126/420 = 630 - 126/420 = 504/420
After reducing the fraction, the answer is 6/5
In mixed form: 11/5

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