Subtract 50/90 from 28/81
28/81 - 50/90 is -17/81.
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,
28/81 = 28 × 10/81 × 10 = 280/810 - Likewise, for the 2nd fraction, since 90 × 9 = 810,
50/90 = 50 × 9/90 × 9 = 450/810 - Subtract the two like fractions:
280/810 - 450/810 = 280 - 450/810 = -170/810 - After reducing the fraction, the answer is -17/81
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