Subtract 20/18 from 15/45
1st number: 15/45, 2nd number: 1 2/18
15/45 - 20/18 is -7/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
15/45 = 15 × 2/45 × 2 = 30/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
20/18 = 20 × 5/18 × 5 = 100/90 - Subtract the two like fractions:
30/90 - 100/90 = 30 - 100/90 = -70/90 - After reducing the fraction, the answer is -7/9
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