Subtract 18/24 from 21/42
21/42 - 18/24 is -1/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
18/24 = 18 × 7/24 × 7 = 126/168 - Subtract the two like fractions:
84/168 - 126/168 = 84 - 126/168 = -42/168 - After reducing the fraction, the answer is -1/4
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