Subtract 81/24 from 30/21
1st number: 1 9/21, 2nd number: 3 9/24
30/21 - 81/24 is -109/56.
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,
30/21 = 30 × 8/21 × 8 = 240/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
81/24 = 81 × 7/24 × 7 = 567/168 - Subtract the two like fractions:
240/168 - 567/168 = 240 - 567/168 = -327/168 - After reducing the fraction, the answer is -109/56
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