Add 63/21 and 80/18, Solve 3 0/21 + 4 8/18 as a fraction

Add 63/21 and 80/18

1^st number: 3 0/21, 2^nd number: 4 8/18

63/21 + 80/18 is 67/9.

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,
63/21 = 63 × 6/21 × 6 = 378/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
80/18 = 80 × 7/18 × 7 = 560/126
Add the two like fractions:
378/126 + 560/126 = 378 + 560/126 = 938/126
938/126 simplified gives 67/9
So, 63/21 + 80/18 = 67/9
In mixed form: 74/9

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