Add 3/21 and 20/18, Solve 3/21 + 1 2/18 as a fraction

Add 3/21 and 20/18

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

3/21 + 20/18 is 79/63.

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,
20/18 = 20 × 7/18 × 7 = 140/126
Add the two like fractions:
18/126 + 140/126 = 18 + 140/126 = 158/126
158/126 simplified gives 79/63
So, 3/21 + 20/18 = 79/63
In mixed form: 116/63

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