ankushbassi wrote:
Bunuel,
Do we need to consider the number of sold copies?
Number of sold copies is not given in question and sounds like an assumption.Can you please help when to consider an information,which is relevant but not provided in the question.
In this case assuming that there was no sales would be an assumption, not vise-versa. Also, notice that the second statement talks about the revenue from the sale, so we know that there was in fact a sale of some number of pads.
Below is my solution for this question. Hope it helps.
At the beginning of last month, a stationery store had in stock 250 writing pads, which had cost the store $0.75 each. During the same month the store made only one purchase of writing pads. What was the total amount spent by the store on the writing pads it had in stock at the end of last month?We are asked to determine the cost of goods in the end of the month.
(1) Last month the store purchased 150 writing pads for $ 0.80 each --> cost of goods at the beginning of the month=0.75*250, plus 150*0.8 store purchased during the month, BUT as long as we don't know how many pads store sold last month we cannot determine the number of pads left at the end of the month. Not sufficient.
(2) Last month the total revenue from the sales of the writing pads was $180. Well this is clearly insufficient. Was any number purchased during the month? What was the selling price of a pad? Not sufficient.
(1)+(2) We know how many and at what price was purchased during the month, plus we are told the revenue was 180, but we don't know the selling price of one pad, thus cannot determine how many was sold and how many left.
Answer: E.
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55% (01:19) correct 
