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

Add 2/21 and 21/18

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

2/21 + 21/18 is 53/42.

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,
2/21 = 2 × 6/21 × 6 = 12/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126
Add the two like fractions:
12/126 + 147/126 = 12 + 147/126 = 159/126
159/126 simplified gives 53/42
So, 2/21 + 21/18 = 53/42
In mixed form: 111/42

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