Add 81/7 and 20/18, Solve 11 4/7 + 1 2/18 as a fraction

Add 81/7 and 20/18

1^st number: 11 4/7, 2^nd number: 1 2/18

81/7 + 20/18 is 799/63.

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,
81/7 = 81 × 18/7 × 18 = 1458/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
20/18 = 20 × 7/18 × 7 = 140/126
Add the two like fractions:
1458/126 + 140/126 = 1458 + 140/126 = 1598/126
1598/126 simplified gives 799/63
So, 81/7 + 20/18 = 799/63
In mixed form: 1243/63

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