Subtract 7/40 from 15/12, Solve 1 3/12

Subtract 7/40 from 15/12

1^st number: 1 3/12, 2^nd number: 7/40

15/12 - 7/40 is 43/40.

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,
15/12 = 15 × 10/12 × 10 = 150/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
7/40 = 7 × 3/40 × 3 = 21/120
Subtract the two like fractions:
150/120 - 21/120 = 150 - 21/120 = 129/120
After reducing the fraction, the answer is 43/40
In mixed form: 13/40

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