Add 21/2 and 90/18
1st number: 10 1/2, 2nd number: 5 0/18
21/2 + 90/18 is 31/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 18 is 18
Next, find the equivalent fraction of both fractional numbers with denominator 18 - For the 1st fraction, since 2 × 9 = 18,
21/2 = 21 × 9/2 × 9 = 189/18 - Likewise, for the 2nd fraction, since 18 × 1 = 18,
90/18 = 90 × 1/18 × 1 = 90/18 - Add the two like fractions:
189/18 + 90/18 = 189 + 90/18 = 279/18 - 279/18 simplified gives 31/2
- So, 21/2 + 90/18 = 31/2
In mixed form: 151/2
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