Subtract 30/60 from 20/45
20/45 - 30/60 is -1/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 60 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
20/45 = 20 × 4/45 × 4 = 80/180 - Likewise, for the 2nd fraction, since 60 × 3 = 180,
30/60 = 30 × 3/60 × 3 = 90/180 - Subtract the two like fractions:
80/180 - 90/180 = 80 - 90/180 = -10/180 - After reducing the fraction, the answer is -1/18
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