Subtract 15/21 from 6/18
6/18 - 15/21 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
6/18 = 6 × 7/18 × 7 = 42/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
15/21 = 15 × 6/21 × 6 = 90/126 - Subtract the two like fractions:
42/126 - 90/126 = 42 - 90/126 = -48/126 - After reducing the fraction, the answer is -8/21
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