Inventory turnover ratio can be calculated by dividing the cost of goods sold by the average inventory. However, as the cost of goods sold is not given in the question, we will use the following formula to calculate inventory turnover ratio:

Inventory turnover ratio = Cost of goods sold / Average inventory

To calculate the average inventory, we need to use the following formula:

Average inventory = (Opening inventory + Closing inventory) / 2

However, the opening inventory is not given in the question, so we will assume that it is equal to the minimum stock level of 1200 units. Therefore, the average inventory can be calculated as follows:

Average inventory = (1200 + Closing inventory) / 2

Now, let's look at the other given information to calculate the closing inventory:

Maximum stock = 9000 units
Order level = 300 units
Reorder quantity = 7800 units
Normal consumption = 300 units per day

From this information, we can determine that:

Maximum inventory = Maximum stock - Order level = 9000 - 300 = 8700 units
Minimum inventory = Minimum stock level = 1200 units
Reorder point = Minimum stock level + Reorder quantity - Normal consumption = 1200 + 7800 - 300 = 8700 units

This means that the closing inventory will be either the maximum inventory of 8700 units or the reorder point of 8700 units, whichever is lower. Therefore, the closing inventory is 8700 units.

Now we can calculate the average inventory as follows:

Average inventory = (1200 + 8700) / 2 = 4950 units

To calculate the inventory turnover ratio, we need to know the cost of goods sold. Without this information, we cannot calculate the ratio.