Subtract 30/81 from 7/40
7/40 - 30/81 is -211/1080.
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,
7/40 = 7 × 81/40 × 81 = 567/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
30/81 = 30 × 40/81 × 40 = 1200/3240 - Subtract the two like fractions:
567/3240 - 1200/3240 = 567 - 1200/3240 = -633/3240 - After reducing the fraction, the answer is -211/1080
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