It is important to clearly understand all the important information's already given in the question. Based on those details the answer to the question can be easily determined.
In 17 hours the number of golf balls hit by Bill = 323
Then
In 1 hour the number of golf balls hit by Bill = (323/17) * 1
= 19
So
The number of golf balls hit by Bill in 23 hours = 23 * 19
= 437
So 437 balls will be hit by Bill in 23 hours. I hope the procedure is clear enough for you to understand. This procedure will help you to solve similar problems in future without requiring any outside help.
