Subtract 72/20 from 5/42, Solve 5/42

Subtract 72/20 from 5/42

1^st number: 5/42, 2^nd number: 3 12/20

5/42 - 72/20 is -731/210.

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,
5/42 = 5 × 10/42 × 10 = 50/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420
Subtract the two like fractions:
50/420 - 1512/420 = 50 - 1512/420 = -1462/420
After reducing the fraction, the answer is -731/210

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