Add 81/42 and 81/30, Solve 1 39/42 + 2 21/30 as a fraction

Add 81/42 and 81/30

1^st number: 1 39/42, 2^nd number: 2 21/30

81/42 + 81/30 is 162/35.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
81/30 = 81 × 7/30 × 7 = 567/210
Add the two like fractions:
405/210 + 567/210 = 405 + 567/210 = 972/210
972/210 simplified gives 162/35
So, 81/42 + 81/30 = 162/35
In mixed form: 422/35

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