Subtract 9/20 from 84/42, Solve 2 0/42

Subtract 9/20 from 84/42

1^st number: 2 0/42, 2^nd number: 9/20

84/42 - 9/20 is 31/20.

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,
84/42 = 84 × 10/42 × 10 = 840/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
9/20 = 9 × 21/20 × 21 = 189/420
Subtract the two like fractions:
840/420 - 189/420 = 840 - 189/420 = 651/420
After reducing the fraction, the answer is 31/20
In mixed form: 111/20

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