Subtract 18/21 from 84/42
1st number: 2 0/42, 2nd number: 18/21
84/42 - 18/21 is 8/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
84/42 = 84 × 1/42 × 1 = 84/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42 - Subtract the two like fractions:
84/42 - 36/42 = 84 - 36/42 = 48/42 - After reducing the fraction, the answer is 8/7
- In mixed form: 11/7
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