Subtract 18/84 from 72/20, Solve 3 12/20

Subtract 18/84 from 72/20

1^st number: 3 12/20, 2^nd number: 18/84

72/20 - 18/84 is 237/70.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420
Subtract the two like fractions:
1512/420 - 90/420 = 1512 - 90/420 = 1422/420
After reducing the fraction, the answer is 237/70
In mixed form: 327/70

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