Subtract 81/15 from 20/24, Solve 20/24

Subtract 81/15 from 20/24

1^st number: 20/24, 2^nd number: 5 6/15

20/24 - 81/15 is -137/30.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 15 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 24 × 5 = 120,
20/24 = 20 × 5/24 × 5 = 100/120
Likewise, for the 2nd fraction, since 15 × 8 = 120,
81/15 = 81 × 8/15 × 8 = 648/120
Subtract the two like fractions:
100/120 - 648/120 = 100 - 648/120 = -548/120
After reducing the fraction, the answer is -137/30

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