Subtract 9/70 from 21/81
21/81 - 9/70 is 247/1890.
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,
21/81 = 21 × 70/81 × 70 = 1470/5670 - Likewise, for the 2nd fraction, since 70 × 81 = 5670,
9/70 = 9 × 81/70 × 81 = 729/5670 - Subtract the two like fractions:
1470/5670 - 729/5670 = 1470 - 729/5670 = 741/5670 - After reducing the fraction, the answer is 247/1890
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