Subtract 21/8 from 15/72
1st number: 15/72, 2nd number: 2 5/8
15/72 - 21/8 is -29/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
15/72 = 15 × 1/72 × 1 = 15/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Subtract the two like fractions:
15/72 - 189/72 = 15 - 189/72 = -174/72 - After reducing the fraction, the answer is -29/12
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