Subtract 20/21 from 18/8
1st number: 2 2/8, 2nd number: 20/21
18/8 - 20/21 is 109/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
18/8 = 18 × 21/8 × 21 = 378/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168 - Subtract the two like fractions:
378/168 - 160/168 = 378 - 160/168 = 218/168 - After reducing the fraction, the answer is 109/84
- In mixed form: 125/84
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