Subtract 70/90 from 70/81
70/81 - 70/90 is 7/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 90 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
70/81 = 70 × 10/81 × 10 = 700/810 - Likewise, for the 2nd fraction, since 90 × 9 = 810,
70/90 = 70 × 9/90 × 9 = 630/810 - Subtract the two like fractions:
700/810 - 630/810 = 700 - 630/810 = 70/810 - After reducing the fraction, the answer is 7/81
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