Add 81/7 and 15/18, Solve 11 4/7 + 15/18 as a fraction

Add 81/7 and 15/18

1^st number: 11 4/7, 2^nd number: 15/18

81/7 + 15/18 is 521/42.

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,
15/18 = 15 × 7/18 × 7 = 105/126
Add the two like fractions:
1458/126 + 105/126 = 1458 + 105/126 = 1563/126
1563/126 simplified gives 521/42
So, 81/7 + 15/18 = 521/42
In mixed form: 1217/42

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