Subtract 20/45 from 9/30
9/30 - 20/45 is -13/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
9/30 = 9 × 3/30 × 3 = 27/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
20/45 = 20 × 2/45 × 2 = 40/90 - Subtract the two like fractions:
27/90 - 40/90 = 27 - 40/90 = -13/90
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