Subtract 21/30 from 12/24, Solve 12/24

Subtract 21/30 from 12/24

12/24 - 21/30 is -1/5.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 30 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 24 × 5 = 120,
12/24 = 12 × 5/24 × 5 = 60/120
Likewise, for the 2nd fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120
Subtract the two like fractions:
60/120 - 84/120 = 60 - 84/120 = -24/120
After reducing the fraction, the answer is -1/5

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