Subtract 28/16 from 21/42
1st number: 21/42, 2nd number: 1 12/16
21/42 - 28/16 is -5/4.
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,
21/42 = 21 × 8/42 × 8 = 168/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
28/16 = 28 × 21/16 × 21 = 588/336 - Subtract the two like fractions:
168/336 - 588/336 = 168 - 588/336 = -420/336 - After reducing the fraction, the answer is -5/4
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