Add 30/18 and 81/7, Solve 1 12/18 + 11 4/7 as a fraction

Add 30/18 and 81/7

1^st number: 1 12/18, 2^nd number: 11 4/7

30/18 + 81/7 is 278/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126
Likewise, for the 2nd fraction, since 7 × 18 = 126,
81/7 = 81 × 18/7 × 18 = 1458/126
Add the two like fractions:
210/126 + 1458/126 = 210 + 1458/126 = 1668/126
1668/126 simplified gives 278/21
So, 30/18 + 81/7 = 278/21
In mixed form: 135/21

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