Subtract 70/63 from 70/81
1st number: 70/81, 2nd number: 1 7/63
70/81 - 70/63 is -20/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 63 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
70/81 = 70 × 7/81 × 7 = 490/567 - Likewise, for the 2nd fraction, since 63 × 9 = 567,
70/63 = 70 × 9/63 × 9 = 630/567 - Subtract the two like fractions:
490/567 - 630/567 = 490 - 630/567 = -140/567 - After reducing the fraction, the answer is -20/81
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