Subtract 21/8 from 90/9
1st number: 10 0/9, 2nd number: 2 5/8
90/9 - 21/8 is 59/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 9 × 8 = 72,
90/9 = 90 × 8/9 × 8 = 720/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Subtract the two like fractions:
720/72 - 189/72 = 720 - 189/72 = 531/72 - After reducing the fraction, the answer is 59/8
- In mixed form: 73/8
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