Subtract 75/20 from 10/42, Solve 10/42

Subtract 75/20 from 10/42

1^st number: 10/42, 2^nd number: 3 15/20

10/42 - 75/20 is -295/84.

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,
10/42 = 10 × 10/42 × 10 = 100/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
75/20 = 75 × 21/20 × 21 = 1575/420
Subtract the two like fractions:
100/420 - 1575/420 = 100 - 1575/420 = -1475/420
After reducing the fraction, the answer is -295/84

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