Subtract 12/9 from 90/42
1st number: 2 6/42, 2nd number: 1 3/9
90/42 - 12/9 is 17/21.
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,
90/42 = 90 × 3/42 × 3 = 270/126 - Likewise, for the 2nd fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126 - Subtract the two like fractions:
270/126 - 168/126 = 270 - 168/126 = 102/126 - After reducing the fraction, the answer is 17/21
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