Add 21/2 and 45/42, Solve 10 1/2 + 1 3/42 as a fraction

Add 21/2 and 45/42

1^st number: 10 1/2, 2^nd number: 1 3/42

21/2 + 45/42 is 81/7.

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,
45/42 = 45 × 1/42 × 1 = 45/42
Add the two like fractions:
441/42 + 45/42 = 441 + 45/42 = 486/42
486/42 simplified gives 81/7
So, 21/2 + 45/42 = 81/7
In mixed form: 114/7

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