Subtract 7/81 from 40/90
40/90 - 7/81 is 29/81.
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,
40/90 = 40 × 9/90 × 9 = 360/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
7/81 = 7 × 10/81 × 10 = 70/810 - Subtract the two like fractions:
360/810 - 70/810 = 360 - 70/810 = 290/810 - After reducing the fraction, the answer is 29/81
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