Subtract 49/81 from 30/70
30/70 - 49/81 is -100/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 81 is 5670
Next, find the equivalent fraction of both fractional numbers with denominator 5670 - For the 1st fraction, since 70 × 81 = 5670,
30/70 = 30 × 81/70 × 81 = 2430/5670 - Likewise, for the 2nd fraction, since 81 × 70 = 5670,
49/81 = 49 × 70/81 × 70 = 3430/5670 - Subtract the two like fractions:
2430/5670 - 3430/5670 = 2430 - 3430/5670 = -1000/5670 - After reducing the fraction, the answer is -100/567
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