Add 21/3 and 80/7, Solve 7 0/3 + 11 3/7 as a fraction

Add 21/3 and 80/7

1^st number: 7 0/3, 2^nd number: 11 3/7

21/3 + 80/7 is 129/7.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 7 is 21

Next, find the equivalent fraction of both fractional numbers with denominator 21
For the 1st fraction, since 3 × 7 = 21,
21/3 = 21 × 7/3 × 7 = 147/21
Likewise, for the 2nd fraction, since 7 × 3 = 21,
80/7 = 80 × 3/7 × 3 = 240/21
Add the two like fractions:
147/21 + 240/21 = 147 + 240/21 = 387/21
387/21 simplified gives 129/7
So, 21/3 + 80/7 = 129/7
In mixed form: 183/7

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