First, change the 3 1/2 and 2/3 to common denominators, meaning that the denominators of both fractions should be the same. So:
3 1/2 = 3 3/6
2/3 = 4/6
Then, just add these two fractions
3 3/6 + 4/6 = 3 7/6
Finally, since this is an improper fraction, change it to a PROPER fraction
3 7/6 = 4 1/6
So, final answer is 4 1/6
I hope this explanation helps! :)
