Add 1/21 and 18/12, Solve 1/21 + 1 6/12 as a fraction

Add 1/21 and 18/12

1^st number: 1/21, 2^nd number: 1 6/12

1/21 + 18/12 is 65/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
1/21 = 1 × 4/21 × 4 = 4/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
18/12 = 18 × 7/12 × 7 = 126/84
Add the two like fractions:
4/84 + 126/84 = 4 + 126/84 = 130/84
130/84 simplified gives 65/42
So, 1/21 + 18/12 = 65/42
In mixed form: 123/42

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