Add 28/30 and 81/42, Solve 28/30 + 1 39/42 as a fraction

Add 28/30 and 81/42

1^st number: 28/30, 2^nd number: 1 39/42

28/30 + 81/42 is 601/210.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
28/30 = 28 × 7/30 × 7 = 196/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210
Add the two like fractions:
196/210 + 405/210 = 196 + 405/210 = 601/210
So, 28/30 + 81/42 = 601/210
In mixed form: 2181/210

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