Answer:
322 shares
Explanation:
When you buy on the margin, your broker will lend you money to purchase the stocks that you need.
Since you have $6,200 on your margin account and your margin requirement is 60%, your maximum purchase = $6,200 / 60% = $10,333.33
With $10,333.33 you can buy ⇒ $10,333.33 / $32 = 322.92 ≈ 322 shares
We have to round down to the last full share.