Subtract 90/8 from 80/21
1st number: 3 17/21, 2nd number: 11 2/8
80/21 - 90/8 is -625/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
80/21 = 80 × 8/21 × 8 = 640/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
90/8 = 90 × 21/8 × 21 = 1890/168 - Subtract the two like fractions:
640/168 - 1890/168 = 640 - 1890/168 = -1250/168 - After reducing the fraction, the answer is -625/84
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