Subtract 90/5 from 21/2
1st number: 10 1/2, 2nd number: 18 0/5
21/2 - 90/5 is -15/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 5 is 10
Next, find the equivalent fraction of both fractional numbers with denominator 10 - For the 1st fraction, since 2 × 5 = 10,
21/2 = 21 × 5/2 × 5 = 105/10 - Likewise, for the 2nd fraction, since 5 × 2 = 10,
90/5 = 90 × 2/5 × 2 = 180/10 - Subtract the two like fractions:
105/10 - 180/10 = 105 - 180/10 = -75/10 - After reducing the fraction, the answer is -15/2
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