Subtract 12/81 from 30/40
30/40 - 12/81 is 65/108.
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,
30/40 = 30 × 81/40 × 81 = 2430/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
12/81 = 12 × 40/81 × 40 = 480/3240 - Subtract the two like fractions:
2430/3240 - 480/3240 = 2430 - 480/3240 = 1950/3240 - After reducing the fraction, the answer is 65/108
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