Subtract 3/9 from 40/42
40/42 - 3/9 is 13/21.
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,
40/42 = 40 × 3/42 × 3 = 120/126 - Likewise, for the 2nd fraction, since 9 × 14 = 126,
3/9 = 3 × 14/9 × 14 = 42/126 - Subtract the two like fractions:
120/126 - 42/126 = 120 - 42/126 = 78/126 - After reducing the fraction, the answer is 13/21
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