Subtract 42/3 from 21/18
1st number: 1 3/18, 2nd number: 14 0/3
21/18 - 42/3 is -77/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 3 is 18
Next, find the equivalent fraction of both fractional numbers with denominator 18 - For the 1st fraction, since 18 × 1 = 18,
21/18 = 21 × 1/18 × 1 = 21/18 - Likewise, for the 2nd fraction, since 3 × 6 = 18,
42/3 = 42 × 6/3 × 6 = 252/18 - Subtract the two like fractions:
21/18 - 252/18 = 21 - 252/18 = -231/18 - After reducing the fraction, the answer is -77/6
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