Add 21/2 and 70/42, Solve 10 1/2 + 1 28/42 as a fraction

Add 21/2 and 70/42

1^st number: 10 1/2, 2^nd number: 1 28/42

21/2 + 70/42 is 73/6.

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,
70/42 = 70 × 1/42 × 1 = 70/42
Add the two like fractions:
441/42 + 70/42 = 441 + 70/42 = 511/42
511/42 simplified gives 73/6
So, 21/2 + 70/42 = 73/6
In mixed form: 121/6

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