Add 18/2 and 54/21
1st number: 9 0/2, 2nd number: 2 12/21
18/2 + 54/21 is 81/7.
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,
54/21 = 54 × 2/21 × 2 = 108/42 - Add the two like fractions:
378/42 + 108/42 = 378 + 108/42 = 486/42 - 486/42 simplified gives 81/7
- So, 18/2 + 54/21 = 81/7
In mixed form: 114/7
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