Subtract 21/5 from 30/18
1st number: 1 12/18, 2nd number: 4 1/5
30/18 - 21/5 is -38/15.
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,
30/18 = 30 × 5/18 × 5 = 150/90 - Likewise, for the 2nd fraction, since 5 × 18 = 90,
21/5 = 21 × 18/5 × 18 = 378/90 - Subtract the two like fractions:
150/90 - 378/90 = 150 - 378/90 = -228/90 - After reducing the fraction, the answer is -38/15
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