Subtract 25/81 from 70/90
70/90 - 25/81 is 38/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
70/90 = 70 × 9/90 × 9 = 630/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
25/81 = 25 × 10/81 × 10 = 250/810 - Subtract the two like fractions:
630/810 - 250/810 = 630 - 250/810 = 380/810 - After reducing the fraction, the answer is 38/81
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