Subtract 81/16 from 20/21
1st number: 20/21, 2nd number: 5 1/16
20/21 - 81/16 is -1381/336.
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,
20/21 = 20 × 16/21 × 16 = 320/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
81/16 = 81 × 21/16 × 21 = 1701/336 - Subtract the two like fractions:
320/336 - 1701/336 = 320 - 1701/336 = -1381/336
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