Subtract 81/45 from 20/12
1st number: 1 8/12, 2nd number: 1 36/45
20/12 - 81/45 is -2/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
20/12 = 20 × 15/12 × 15 = 300/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
81/45 = 81 × 4/45 × 4 = 324/180 - Subtract the two like fractions:
300/180 - 324/180 = 300 - 324/180 = -24/180 - After reducing the fraction, the answer is -2/15
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