Subtract 42/40 from 8/81
1st number: 8/81, 2nd number: 1 2/40
8/81 - 42/40 is -1541/1620.
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,
8/81 = 8 × 40/81 × 40 = 320/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
42/40 = 42 × 81/40 × 81 = 3402/3240 - Subtract the two like fractions:
320/3240 - 3402/3240 = 320 - 3402/3240 = -3082/3240 - After reducing the fraction, the answer is -1541/1620
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