Subtract 18/9 from 21/42
1st number: 21/42, 2nd number: 2 0/9
21/42 - 18/9 is -3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Likewise, for the 2nd fraction, since 9 × 14 = 126,
18/9 = 18 × 14/9 × 14 = 252/126 - Subtract the two like fractions:
63/126 - 252/126 = 63 - 252/126 = -189/126 - After reducing the fraction, the answer is -3/2
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