Subtract 12/9 from 21/72
1st number: 21/72, 2nd number: 1 3/9
21/72 - 12/9 is -25/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
12/9 = 12 × 8/9 × 8 = 96/72 - Subtract the two like fractions:
21/72 - 96/72 = 21 - 96/72 = -75/72 - After reducing the fraction, the answer is -25/24
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