Subtract 20/16 from 18/21
1st number: 18/21, 2nd number: 1 4/16
18/21 - 20/16 is -11/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 16 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 21 × 16 = 336,
18/21 = 18 × 16/21 × 16 = 288/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
20/16 = 20 × 21/16 × 21 = 420/336 - Subtract the two like fractions:
288/336 - 420/336 = 288 - 420/336 = -132/336 - After reducing the fraction, the answer is -11/28
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