Subtract 20/12 from 21/72
1st number: 21/72, 2nd number: 1 8/12
21/72 - 20/12 is -11/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 12 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 12 × 6 = 72,
20/12 = 20 × 6/12 × 6 = 120/72 - Subtract the two like fractions:
21/72 - 120/72 = 21 - 120/72 = -99/72 - After reducing the fraction, the answer is -11/8
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