Add 21/2 and 84/42, Solve 10 1/2 + 2 0/42 as a fraction

Add 21/2 and 84/42

1^st number: 10 1/2, 2^nd number: 2 0/42

21/2 + 84/42 is 25/2.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 42 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 42 × 1 = 42,
84/42 = 84 × 1/42 × 1 = 84/42
Add the two like fractions:
441/42 + 84/42 = 441 + 84/42 = 525/42
525/42 simplified gives 25/2
So, 21/2 + 84/42 = 25/2
In mixed form: 121/2

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