Subtract 21/5 from 20/18
1st number: 1 2/18, 2nd number: 4 1/5
20/18 - 21/5 is -139/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 5 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
20/18 = 20 × 5/18 × 5 = 100/90 - Likewise, for the 2nd fraction, since 5 × 18 = 90,
21/5 = 21 × 18/5 × 18 = 378/90 - Subtract the two like fractions:
100/90 - 378/90 = 100 - 378/90 = -278/90 - After reducing the fraction, the answer is -139/45
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