Add 18/2 and 81/21
1st number: 9 0/2, 2nd number: 3 18/21
18/2 + 81/21 is 90/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
18/2 = 18 × 21/2 × 21 = 378/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42 - Add the two like fractions:
378/42 + 162/42 = 378 + 162/42 = 540/42 - 540/42 simplified gives 90/7
- So, 18/2 + 81/21 = 90/7
In mixed form: 126/7
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