Subtract 75/90 from 18/45
18/45 - 75/90 is -13/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
18/45 = 18 × 2/45 × 2 = 36/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
75/90 = 75 × 1/90 × 1 = 75/90 - Subtract the two like fractions:
36/90 - 75/90 = 36 - 75/90 = -39/90 - After reducing the fraction, the answer is -13/30
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