Subtract 40/18 from 42/21
1st number: 2 0/21, 2nd number: 2 4/18
42/21 - 40/18 is -2/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
42/21 = 42 × 6/21 × 6 = 252/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
40/18 = 40 × 7/18 × 7 = 280/126 - Subtract the two like fractions:
252/126 - 280/126 = 252 - 280/126 = -28/126 - After reducing the fraction, the answer is -2/9
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