Subtract 20/42 from 18/24
18/24 - 20/42 is 23/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 24 × 7 = 168,
18/24 = 18 × 7/24 × 7 = 126/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
20/42 = 20 × 4/42 × 4 = 80/168 - Subtract the two like fractions:
126/168 - 80/168 = 126 - 80/168 = 46/168 - After reducing the fraction, the answer is 23/84
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