Subtract 42/81 from 90/40
1st number: 2 10/40, 2nd number: 42/81
90/40 - 42/81 is 187/108.
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,
90/40 = 90 × 81/40 × 81 = 7290/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
42/81 = 42 × 40/81 × 40 = 1680/3240 - Subtract the two like fractions:
7290/3240 - 1680/3240 = 7290 - 1680/3240 = 5610/3240 - After reducing the fraction, the answer is 187/108
- In mixed form: 179/108
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