Subtract 28/24 from 18/21
1st number: 18/21, 2nd number: 1 4/24
18/21 - 28/24 is -13/42.
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,
18/21 = 18 × 8/21 × 8 = 144/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
28/24 = 28 × 7/24 × 7 = 196/168 - Subtract the two like fractions:
144/168 - 196/168 = 144 - 196/168 = -52/168 - After reducing the fraction, the answer is -13/42
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