Add 9/18 and 80/21, Solve 9/18 + 3 17/21 as a fraction

Add 9/18 and 80/21

1^st number: 9/18, 2^nd number: 3 17/21

9/18 + 80/21 is 181/42.

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,
9/18 = 9 × 7/18 × 7 = 63/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
80/21 = 80 × 6/21 × 6 = 480/126
Add the two like fractions:
63/126 + 480/126 = 63 + 480/126 = 543/126
543/126 simplified gives 181/42
So, 9/18 + 80/21 = 181/42
In mixed form: 413/42

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