Subtract 18/21 from 20/24
20/24 - 18/21 is -1/42.
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,
20/24 = 20 × 7/24 × 7 = 140/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168 - Subtract the two like fractions:
140/168 - 144/168 = 140 - 144/168 = -4/168 - After reducing the fraction, the answer is -1/42
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