Subtract 3/12 from 20/90
20/90 - 3/12 is -1/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
20/90 = 20 × 2/90 × 2 = 40/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
3/12 = 3 × 15/12 × 15 = 45/180 - Subtract the two like fractions:
40/180 - 45/180 = 40 - 45/180 = -5/180 - After reducing the fraction, the answer is -1/36
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