Subtract 18/42 from 21/3
1st number: 7 0/3, 2nd number: 18/42
21/3 - 18/42 is 46/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 3 × 14 = 42,
21/3 = 21 × 14/3 × 14 = 294/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Subtract the two like fractions:
294/42 - 18/42 = 294 - 18/42 = 276/42 - After reducing the fraction, the answer is 46/7
- In mixed form: 64/7
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