Subtract 28/21 from 21/24
1st number: 21/24, 2nd number: 1 7/21
21/24 - 28/21 is -11/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
28/21 = 28 × 8/21 × 8 = 224/168 - Subtract the two like fractions:
147/168 - 224/168 = 147 - 224/168 = -77/168 - After reducing the fraction, the answer is -11/24
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