Add 15/42 and 80/30, Solve 15/42 + 2 20/30 as a fraction

Add 15/42 and 80/30

1^st number: 15/42, 2^nd number: 2 20/30

15/42 + 80/30 is 127/42.

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,
15/42 = 15 × 5/42 × 5 = 75/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
80/30 = 80 × 7/30 × 7 = 560/210
Add the two like fractions:
75/210 + 560/210 = 75 + 560/210 = 635/210
635/210 simplified gives 127/42
So, 15/42 + 80/30 = 127/42
In mixed form: 31/42

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