Add 21/7 and 15/18, Solve 3 0/7 + 15/18 as a fraction

Add 21/7 and 15/18

1^st number: 3 0/7, 2^nd number: 15/18

21/7 + 15/18 is 23/6.

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,
15/18 = 15 × 7/18 × 7 = 105/126
Add the two like fractions:
378/126 + 105/126 = 378 + 105/126 = 483/126
483/126 simplified gives 23/6
So, 21/7 + 15/18 = 23/6
In mixed form: 35/6

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