Subtract 81/90 from 7/2
1st number: 3 1/2, 2nd number: 81/90
7/2 - 81/90 is 13/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 2 × 45 = 90,
7/2 = 7 × 45/2 × 45 = 315/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
81/90 = 81 × 1/90 × 1 = 81/90 - Subtract the two like fractions:
315/90 - 81/90 = 315 - 81/90 = 234/90 - After reducing the fraction, the answer is 13/5
- In mixed form: 23/5
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