Subtract 50/90 from 42/81
42/81 - 50/90 is -1/27.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 90 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
42/81 = 42 × 10/81 × 10 = 420/810 - Likewise, for the 2nd fraction, since 90 × 9 = 810,
50/90 = 50 × 9/90 × 9 = 450/810 - Subtract the two like fractions:
420/810 - 450/810 = 420 - 450/810 = -30/810 - After reducing the fraction, the answer is -1/27
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