Subtract 12/5 from 21/24, Solve 21/24

Subtract 12/5 from 21/24

1^st number: 21/24, 2^nd number: 2 2/5

21/24 - 12/5 is -61/40.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 5 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 24 × 5 = 120,
21/24 = 21 × 5/24 × 5 = 105/120
Likewise, for the 2nd fraction, since 5 × 24 = 120,
12/5 = 12 × 24/5 × 24 = 288/120
Subtract the two like fractions:
105/120 - 288/120 = 105 - 288/120 = -183/120
After reducing the fraction, the answer is -61/40

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