ANSWER
15 shots
Step-by-step explanation
Klay has made 1/3 of his attempted shots.
Let the number of attempted shots be x.
This means that he has made:
1/3 * x = x/3
If he makes his next 5 shots, his shooting percentage will increase to 50%. In other words, he will have made half hsi attempted shots.
Adding 5 shots to the shots he already attempted before is:
x + 5
So, now, he would have made:
1/2 * (x + 5)
This is the same as adding the number of shots he had made before to the number of shots he has made now. That is:
This means that he had attempted 15 shots when he was at 1/3 success rate.