Add 30/21 and 80/42, Solve 1 9/21 + 1 38/42 as a fraction

Add 30/21 and 80/42

1^st number: 1 9/21, 2^nd number: 1 38/42

30/21 + 80/42 is 10/3.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
30/21 = 30 × 2/21 × 2 = 60/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
80/42 = 80 × 1/42 × 1 = 80/42
Add the two like fractions:
60/42 + 80/42 = 60 + 80/42 = 140/42
140/42 simplified gives 10/3
So, 30/21 + 80/42 = 10/3
In mixed form: 31/3

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