Subtract 30/81 from 20/40
20/40 - 30/81 is 7/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 81 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 40 × 81 = 3240,
20/40 = 20 × 81/40 × 81 = 1620/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
30/81 = 30 × 40/81 × 40 = 1200/3240 - Subtract the two like fractions:
1620/3240 - 1200/3240 = 1620 - 1200/3240 = 420/3240 - After reducing the fraction, the answer is 7/54
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