Subtract 42/40 from 28/81
1st number: 28/81, 2nd number: 1 2/40
28/81 - 42/40 is -1141/1620.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 40 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 81 × 40 = 3240,
28/81 = 28 × 40/81 × 40 = 1120/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
42/40 = 42 × 81/40 × 81 = 3402/3240 - Subtract the two like fractions:
1120/3240 - 3402/3240 = 1120 - 3402/3240 = -2282/3240 - After reducing the fraction, the answer is -1141/1620
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