Add 20/18 and 80/21, Solve 1 2/18 + 3 17/21 as a fraction

Add 20/18 and 80/21

1^st number: 1 2/18, 2^nd number: 3 17/21

20/18 + 80/21 is 310/63.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
20/18 = 20 × 7/18 × 7 = 140/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
80/21 = 80 × 6/21 × 6 = 480/126
Add the two like fractions:
140/126 + 480/126 = 140 + 480/126 = 620/126
620/126 simplified gives 310/63
So, 20/18 + 80/21 = 310/63
In mixed form: 458/63

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