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

Add 3/21 and 42/18

1^st number: 3/21, 2^nd number: 2 6/18

3/21 + 42/18 is 52/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
3/21 = 3 × 6/21 × 6 = 18/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
42/18 = 42 × 7/18 × 7 = 294/126
Add the two like fractions:
18/126 + 294/126 = 18 + 294/126 = 312/126
312/126 simplified gives 52/21
So, 3/21 + 42/18 = 52/21
In mixed form: 210/21

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