Add 21/2 and 18/21, Solve 10 1/2 + 18/21 as a fraction

Add 21/2 and 18/21

1^st number: 10 1/2, 2^nd number: 18/21

21/2 + 18/21 is 159/14.

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,
21/2 = 21 × 21/2 × 21 = 441/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42
Add the two like fractions:
441/42 + 36/42 = 441 + 36/42 = 477/42
477/42 simplified gives 159/14
So, 21/2 + 18/21 = 159/14
In mixed form: 115/14

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