Subtract 63/40 from 42/12, Solve 3 6/12

Subtract 63/40 from 42/12

1^st number: 3 6/12, 2^nd number: 1 23/40

42/12 - 63/40 is 77/40.

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

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 12 × 10 = 120,
42/12 = 42 × 10/12 × 10 = 420/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
63/40 = 63 × 3/40 × 3 = 189/120
Subtract the two like fractions:
420/120 - 189/120 = 420 - 189/120 = 231/120
After reducing the fraction, the answer is 77/40
In mixed form: 137/40

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