Subtract 60/42 from 15/40, Solve 15/40

Subtract 60/42 from 15/40

1^st number: 15/40, 2^nd number: 1 18/42

15/40 - 60/42 is -59/56.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
15/40 = 15 × 21/40 × 21 = 315/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
60/42 = 60 × 20/42 × 20 = 1200/840
Subtract the two like fractions:
315/840 - 1200/840 = 315 - 1200/840 = -885/840
After reducing the fraction, the answer is -59/56

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