Subtract 40/7 from 20/81
1st number: 20/81, 2nd number: 5 5/7
20/81 - 40/7 is -3100/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 7 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
20/81 = 20 × 7/81 × 7 = 140/567 - Likewise, for the 2nd fraction, since 7 × 81 = 567,
40/7 = 40 × 81/7 × 81 = 3240/567 - Subtract the two like fractions:
140/567 - 3240/567 = 140 - 3240/567 = -3100/567
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