Subtract 10/21 from 81/63
1st number: 1 18/63, 2nd number: 10/21
81/63 - 10/21 is 17/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 63 × 1 = 63,
81/63 = 81 × 1/63 × 1 = 81/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
10/21 = 10 × 3/21 × 3 = 30/63 - Subtract the two like fractions:
81/63 - 30/63 = 81 - 30/63 = 51/63 - After reducing the fraction, the answer is 17/21
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