Subtract 9/42 from 21/18
1st number: 1 3/18, 2nd number: 9/42
21/18 - 9/42 is 20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
9/42 = 9 × 3/42 × 3 = 27/126 - Subtract the two like fractions:
147/126 - 27/126 = 147 - 27/126 = 120/126 - After reducing the fraction, the answer is 20/21
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