Subtract 21/24 from 15/21
15/21 - 21/24 is -9/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
15/21 = 15 × 8/21 × 8 = 120/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168 - Subtract the two like fractions:
120/168 - 147/168 = 120 - 147/168 = -27/168 - After reducing the fraction, the answer is -9/56
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