Add 80/21 and 60/18, Solve 3 17/21 + 3 6/18 as a fraction

Add 80/21 and 60/18

1^st number: 3 17/21, 2^nd number: 3 6/18

80/21 + 60/18 is 50/7.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
80/21 = 80 × 6/21 × 6 = 480/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
60/18 = 60 × 7/18 × 7 = 420/126
Add the two like fractions:
480/126 + 420/126 = 480 + 420/126 = 900/126
900/126 simplified gives 50/7
So, 80/21 + 60/18 = 50/7
In mixed form: 71/7

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