I got the answer 3 19/24.
To make it easier, ignore the whole number 3 and just focus on 3/8 and 5/12.
Their common denominator is 24.
8 can go into 24, 3 times and 3x3 is 9.
So now you have 9/24.
Then you do the same to the other fraction.
12 can go into 24 twice and 5x2 is 10. So your new fraction is 10/24. So you add up both fractions, 9/24 and 10/24 and get 19/24. Lastly you add your whole number which is 3 so now your answer is 3 19/24. I hope that was helpful I'm sorry there were so many number.