Subtract 81/90 from 15/50
15/50 - 81/90 is -3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 50 × 9 = 450,
15/50 = 15 × 9/50 × 9 = 135/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
81/90 = 81 × 5/90 × 5 = 405/450 - Subtract the two like fractions:
135/450 - 405/450 = 135 - 405/450 = -270/450 - After reducing the fraction, the answer is -3/5
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