Subtract 9/81 from 1/70, Solve 1/70

Subtract 9/81 from 1/70

1/70 - 9/81 is -61/630.

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,
1/70 = 1 × 81/70 × 81 = 81/5670
Likewise, for the 2nd fraction, since 81 × 70 = 5670,
9/81 = 9 × 70/81 × 70 = 630/5670
Subtract the two like fractions:
81/5670 - 630/5670 = 81 - 630/5670 = -549/5670
After reducing the fraction, the answer is -61/630

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