Subtract 21/24 from 18/28
18/28 - 21/24 is -13/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 28 × 6 = 168,
18/28 = 18 × 6/28 × 6 = 108/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168 - Subtract the two like fractions:
108/168 - 147/168 = 108 - 147/168 = -39/168 - After reducing the fraction, the answer is -13/56
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