Subtract 5/42 from 21/18
1st number: 1 3/18, 2nd number: 5/42
21/18 - 5/42 is 22/21.
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,
5/42 = 5 × 3/42 × 3 = 15/126 - Subtract the two like fractions:
147/126 - 15/126 = 147 - 15/126 = 132/126 - After reducing the fraction, the answer is 22/21
- In mixed form: 11/21
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