Subtract 40/42 from 12/9
1st number: 1 3/9, 2nd number: 40/42
12/9 - 40/42 is 8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
40/42 = 40 × 3/42 × 3 = 120/126 - Subtract the two like fractions:
168/126 - 120/126 = 168 - 120/126 = 48/126 - After reducing the fraction, the answer is 8/21
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