Assuming no safety stock, what is the reorder point (R) given an average daily demand of 78 units and a lead time of 3 days?

I agree to both of above replies and would like to add the following as well from a reply given by Mostafa Abouelsaad to a very similar question earlier:  

Quote:

However you should also consider the following factors before ordering:

• Is there a minimum order quantity for the needed units?
• Is it a seasonal product?
• Is your Purchasing budget enough for the needed units?

Unquote

By multiplication of figures -------------

You will need to multiply both numbers together to get the final figure.  This is your safety stock.