Subtract 42/24 from 8/21
1st number: 8/21, 2nd number: 1 18/24
8/21 - 42/24 is -115/84.
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,
8/21 = 8 × 8/21 × 8 = 64/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
42/24 = 42 × 7/24 × 7 = 294/168 - Subtract the two like fractions:
64/168 - 294/168 = 64 - 294/168 = -230/168 - After reducing the fraction, the answer is -115/84
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