Subtract 4/81 from 42/40
1st number: 1 2/40, 2nd number: 4/81
42/40 - 4/81 is 1621/1620.
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,
42/40 = 42 × 81/40 × 81 = 3402/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
4/81 = 4 × 40/81 × 40 = 160/3240 - Subtract the two like fractions:
3402/3240 - 160/3240 = 3402 - 160/3240 = 3242/3240 - After reducing the fraction, the answer is 1621/1620
- In mixed form: 11/1620
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