Add 21/14 and 28/18, Solve 1 7/14 + 1 10/18 as a fraction

Add 21/14 and 28/18

1^st number: 1 7/14, 2^nd number: 1 10/18

21/14 + 28/18 is 55/18.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 18 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 18 × 7 = 126,
28/18 = 28 × 7/18 × 7 = 196/126
Add the two like fractions:
189/126 + 196/126 = 189 + 196/126 = 385/126
385/126 simplified gives 55/18
So, 21/14 + 28/18 = 55/18
In mixed form: 31/18

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