Subtract 90/81 from 40/30
1st number: 1 10/30, 2nd number: 1 9/81
40/30 - 90/81 is 2/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
40/30 = 40 × 27/30 × 27 = 1080/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
90/81 = 90 × 10/81 × 10 = 900/810 - Subtract the two like fractions:
1080/810 - 900/810 = 1080 - 900/810 = 180/810 - After reducing the fraction, the answer is 2/9
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