Subtract 30/18 from 20/15
1st number: 1 5/15, 2nd number: 1 12/18
20/15 - 30/18 is -1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
20/15 = 20 × 6/15 × 6 = 120/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
30/18 = 30 × 5/18 × 5 = 150/90 - Subtract the two like fractions:
120/90 - 150/90 = 120 - 150/90 = -30/90 - After reducing the fraction, the answer is -1/3
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