Add 21/14 and 18/9, Solve 1 7/14 + 2 0/9 as a fraction

Add 21/14 and 18/9

1^st number: 1 7/14, 2^nd number: 2 0/9

21/14 + 18/9 is 7/2.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 9 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 14 × 9 = 126,
21/14 = 21 × 9/14 × 9 = 189/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
18/9 = 18 × 14/9 × 14 = 252/126
Add the two like fractions:
189/126 + 252/126 = 189 + 252/126 = 441/126
441/126 simplified gives 7/2
So, 21/14 + 18/9 = 7/2
In mixed form: 31/2

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