Subtract 4/21 from 42/18
1st number: 2 6/18, 2nd number: 4/21
42/18 - 4/21 is 15/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
42/18 = 42 × 7/18 × 7 = 294/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
4/21 = 4 × 6/21 × 6 = 24/126 - Subtract the two like fractions:
294/126 - 24/126 = 294 - 24/126 = 270/126 - After reducing the fraction, the answer is 15/7
- In mixed form: 21/7
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