Subtract 63/40 from 15/30, Solve 15/30

Subtract 63/40 from 15/30

1^st number: 15/30, 2^nd number: 1 23/40

15/30 - 63/40 is -43/40.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 30 × 4 = 120,
15/30 = 15 × 4/30 × 4 = 60/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
63/40 = 63 × 3/40 × 3 = 189/120
Subtract the two like fractions:
60/120 - 189/120 = 60 - 189/120 = -129/120
After reducing the fraction, the answer is -43/40

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