It was stated that only thirty percent of all customers who enter a store will make a purchase and it was not mentioned whether it is independent or dependent purchase decisions. Suppose, there six customers entered the store and since the thirty percent of this is 2 heads. Therefore, out of 6 customers, only 2 persons will purchase.
262.6/300% for the first 3 test if you were to add another test it would be 400% total and you need 360% of test grades to have an average of 90% and so 360 - 262.6 = 97.4%
