Add 21/7 and 42/18, Solve 3 0/7 + 2 6/18 as a fraction

Add 21/7 and 42/18

1^st number: 3 0/7, 2^nd number: 2 6/18

21/7 + 42/18 is 16/3.

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,
21/7 = 21 × 18/7 × 18 = 378/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
42/18 = 42 × 7/18 × 7 = 294/126
Add the two like fractions:
378/126 + 294/126 = 378 + 294/126 = 672/126
672/126 simplified gives 16/3
So, 21/7 + 42/18 = 16/3
In mixed form: 51/3

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