Subtract 80/90 from 15/75
15/75 - 80/90 is -31/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 75 × 6 = 450,
15/75 = 15 × 6/75 × 6 = 90/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
80/90 = 80 × 5/90 × 5 = 400/450 - Subtract the two like fractions:
90/450 - 400/450 = 90 - 400/450 = -310/450 - After reducing the fraction, the answer is -31/45
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