Subtract 20/12 from 15/90
1st number: 15/90, 2nd number: 1 8/12
15/90 - 20/12 is -3/2.
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,
15/90 = 15 × 2/90 × 2 = 30/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
20/12 = 20 × 15/12 × 15 = 300/180 - Subtract the two like fractions:
30/180 - 300/180 = 30 - 300/180 = -270/180 - After reducing the fraction, the answer is -3/2
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