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

Add 21/10 and 28/42

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

21/10 + 28/42 is 83/30.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
21/10 = 21 × 21/10 × 21 = 441/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
28/42 = 28 × 5/42 × 5 = 140/210
Add the two like fractions:
441/210 + 140/210 = 441 + 140/210 = 581/210
581/210 simplified gives 83/30
So, 21/10 + 28/42 = 83/30
In mixed form: 223/30

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