Subtract 40/21 from 18/4
1st number: 4 2/4, 2nd number: 1 19/21
18/4 - 40/21 is 109/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
18/4 = 18 × 21/4 × 21 = 378/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
40/21 = 40 × 4/21 × 4 = 160/84 - Subtract the two like fractions:
378/84 - 160/84 = 378 - 160/84 = 218/84 - After reducing the fraction, the answer is 109/42
- In mixed form: 225/42
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