Subtract 42/10 from 40/81
1st number: 40/81, 2nd number: 4 2/10
40/81 - 42/10 is -1501/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 10 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
40/81 = 40 × 10/81 × 10 = 400/810 - Likewise, for the 2nd fraction, since 10 × 81 = 810,
42/10 = 42 × 81/10 × 81 = 3402/810 - Subtract the two like fractions:
400/810 - 3402/810 = 400 - 3402/810 = -3002/810 - After reducing the fraction, the answer is -1501/405
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