Add 21/2 and 84/21, Solve 10 1/2 + 4 0/21 as a fraction

Add 21/2 and 84/21

1^st number: 10 1/2, 2^nd number: 4 0/21

21/2 + 84/21 is 29/2.

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,
84/21 = 84 × 2/21 × 2 = 168/42
Add the two like fractions:
441/42 + 168/42 = 441 + 168/42 = 609/42
609/42 simplified gives 29/2
So, 21/2 + 84/21 = 29/2
In mixed form: 141/2

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