Final answer:
Joe can buy 175 shares of XYZ Corporation with his savings and the transaction fee.
Step-by-step explanation:
To calculate the number of shares Joe can buy, we need to first subtract the transaction fee from his savings. In this case, the transaction fee is $50. So, Joe's remaining savings will be $4,000 - $50 = $3,950.
Next, we divide the remaining savings by the current price per share to find the number of shares Joe can buy. Joe can buy $3,950 / $22.50 = 175.56 shares.
Since we can't purchase a fraction of a share, Joe can buy a maximum of 175 shares of XYZ Corporation with his savings and the transaction fee.