Subtract 18/42 from 21/9
1st number: 2 3/9, 2nd number: 18/42
21/9 - 18/42 is 40/21.
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,
21/9 = 21 × 14/9 × 14 = 294/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
18/42 = 18 × 3/42 × 3 = 54/126 - Subtract the two like fractions:
294/126 - 54/126 = 294 - 54/126 = 240/126 - After reducing the fraction, the answer is 40/21
- In mixed form: 119/21
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