Subtract 21/15 from 21/18
1st number: 1 3/18, 2nd number: 1 6/15
21/18 - 21/15 is -7/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 15 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Likewise, for the 2nd fraction, since 15 × 6 = 90,
21/15 = 21 × 6/15 × 6 = 126/90 - Subtract the two like fractions:
105/90 - 126/90 = 105 - 126/90 = -21/90 - After reducing the fraction, the answer is -7/30
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