Add 27/18 and 80/21, Solve 1 9/18 + 3 17/21 as a fraction

Add 27/18 and 80/21

1^st number: 1 9/18, 2^nd number: 3 17/21

27/18 + 80/21 is 223/42.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
27/18 = 27 × 7/18 × 7 = 189/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
80/21 = 80 × 6/21 × 6 = 480/126
Add the two like fractions:
189/126 + 480/126 = 189 + 480/126 = 669/126
669/126 simplified gives 223/42
So, 27/18 + 80/21 = 223/42
In mixed form: 513/42

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