Subtract 20/16 from 18/42
1st number: 18/42, 2nd number: 1 4/16
18/42 - 20/16 is -23/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 16 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 42 × 8 = 336,
18/42 = 18 × 8/42 × 8 = 144/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
20/16 = 20 × 21/16 × 21 = 420/336 - Subtract the two like fractions:
144/336 - 420/336 = 144 - 420/336 = -276/336 - After reducing the fraction, the answer is -23/28
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