Subtract 84/81 from 28/40
1st number: 28/40, 2nd number: 1 3/81
28/40 - 84/81 is -91/270.
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,
28/40 = 28 × 81/40 × 81 = 2268/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
84/81 = 84 × 40/81 × 40 = 3360/3240 - Subtract the two like fractions:
2268/3240 - 3360/3240 = 2268 - 3360/3240 = -1092/3240 - After reducing the fraction, the answer is -91/270
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