Subtract 21/16 from 20/42
1st number: 20/42, 2nd number: 1 5/16
20/42 - 21/16 is -281/336.
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,
20/42 = 20 × 8/42 × 8 = 160/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
21/16 = 21 × 21/16 × 21 = 441/336 - Subtract the two like fractions:
160/336 - 441/336 = 160 - 441/336 = -281/336
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