Subtract 12/45 from 7/90
7/90 - 12/45 is -17/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
7/90 = 7 × 1/90 × 1 = 7/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
12/45 = 12 × 2/45 × 2 = 24/90 - Subtract the two like fractions:
7/90 - 24/90 = 7 - 24/90 = -17/90
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