Subtract 63/12 from 42/40, Solve 1 2/40

Subtract 63/12 from 42/40

1^st number: 1 2/40, 2^nd number: 5 3/12

42/40 - 63/12 is -21/5.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 12 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
42/40 = 42 × 3/40 × 3 = 126/120
Likewise, for the 2nd fraction, since 12 × 10 = 120,
63/12 = 63 × 10/12 × 10 = 630/120
Subtract the two like fractions:
126/120 - 630/120 = 126 - 630/120 = -504/120
After reducing the fraction, the answer is -21/5

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