Subtract 15/16 from 42/21
1st number: 2 0/21, 2nd number: 15/16
42/21 - 15/16 is 17/16.
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,
42/21 = 42 × 16/21 × 16 = 672/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
15/16 = 15 × 21/16 × 21 = 315/336 - Subtract the two like fractions:
672/336 - 315/336 = 672 - 315/336 = 357/336 - After reducing the fraction, the answer is 17/16
- In mixed form: 11/16
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