Subtract 40/81 from 81/30
1st number: 2 21/30, 2nd number: 40/81
81/30 - 40/81 is 1787/810.
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,
81/30 = 81 × 27/30 × 27 = 2187/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
40/81 = 40 × 10/81 × 10 = 400/810 - Subtract the two like fractions:
2187/810 - 400/810 = 2187 - 400/810 = 1787/810 - In mixed form: 2167/810
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