Subtract 70/81 from 42/21
1st number: 2 0/21, 2nd number: 70/81
42/21 - 70/81 is 92/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
42/21 = 42 × 27/21 × 27 = 1134/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
70/81 = 70 × 7/81 × 7 = 490/567 - Subtract the two like fractions:
1134/567 - 490/567 = 1134 - 490/567 = 644/567 - After reducing the fraction, the answer is 92/81
- In mixed form: 111/81
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