Add 80/7 and 30/18, Solve 11 3/7 + 1 12/18 as a fraction

Add 80/7 and 30/18

1^st number: 11 3/7, 2^nd number: 1 12/18

80/7 + 30/18 is 275/21.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 7 × 18 = 126,
80/7 = 80 × 18/7 × 18 = 1440/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126
Add the two like fractions:
1440/126 + 210/126 = 1440 + 210/126 = 1650/126
1650/126 simplified gives 275/21
So, 80/7 + 30/18 = 275/21
In mixed form: 132/21

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