Subtract 20/21 from 15/16
15/16 - 20/21 is -5/336.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 21 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 16 × 21 = 336,
15/16 = 15 × 21/16 × 21 = 315/336 - Likewise, for the 2nd fraction, since 21 × 16 = 336,
20/21 = 20 × 16/21 × 16 = 320/336 - Subtract the two like fractions:
315/336 - 320/336 = 315 - 320/336 = -5/336
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