Subtract 18/70 from 7/81
7/81 - 18/70 is -484/2835.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 70 is 5670
Next, find the equivalent fraction of both fractional numbers with denominator 5670 - For the 1st fraction, since 81 × 70 = 5670,
7/81 = 7 × 70/81 × 70 = 490/5670 - Likewise, for the 2nd fraction, since 70 × 81 = 5670,
18/70 = 18 × 81/70 × 81 = 1458/5670 - Subtract the two like fractions:
490/5670 - 1458/5670 = 490 - 1458/5670 = -968/5670 - After reducing the fraction, the answer is -484/2835
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