Subtract 18/81 from 12/40
12/40 - 18/81 is 7/90.
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,
12/40 = 12 × 81/40 × 81 = 972/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
18/81 = 18 × 40/81 × 40 = 720/3240 - Subtract the two like fractions:
972/3240 - 720/3240 = 972 - 720/3240 = 252/3240 - After reducing the fraction, the answer is 7/90
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