Subtract 20/21 from 90/8
1st number: 11 2/8, 2nd number: 20/21
90/8 - 20/21 is 865/84.
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,
90/8 = 90 × 21/8 × 21 = 1890/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168 - Subtract the two like fractions:
1890/168 - 160/168 = 1890 - 160/168 = 1730/168 - After reducing the fraction, the answer is 865/84
- In mixed form: 1025/84
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