A photography dealer ordered 60 Model X cameras to be sold for $250 each, which represents a 20 percent markup over the dealer’s initial cost for each camera. Of the cameras ordered, 6 were never sold and were returned to the manufacturer for a refund of 50 percent of the dealer's initial cost. What was the dealer's approximate profit or loss as a percent of the dealer’s initial cost for the 60 cameras?
I agree with the different approaches discussed here, especially the weighted average one. So thought of discussing some time-saving tips here.
The cost price of each model X camera is the same. So let it be CP.
Note:
Whenever you solve questions based on 2 or more different transactions , it is very easy to find the overall profit/Loss % if the cost price is the same for every products involved.Do you need to find CP here to answer this question?
Not really.
Finding CP and solving this question would cost you a lot of time. Let us try a logical approach instead.
Overall profit/loss % = (Overall profit/loss)/Total_cost * 100
Overall profit /loss can be expressed in terms of CP as the profit% and loss % are given.
Since CP is common in both numerator and denominator, it will get canceled during the calculation. So, the value of CP will not be needed to get the final answer.
This will give you the freedom to completely disregard CP or plugin a suitable value of your preference for CP. Either way around, the final answer will not change.
Let's analyze in detail .
54 cameras are sold at 20 % profit and 6 cameras are sold at a loss of 50 %.
Overall profit/loss = 20 % of (54*CP) - 50 % of (6 * CP)
Profit /Loss % = (20 % of (54CP) - 50 % of (6 CP))/ (60 CP ) *100
CP will get canceled and it will not affect your final answer. Hence, we don't need to find the value of CP here.
Profit /Loss % = (20 % of 54 - 50 % of 6 )/ 60 *100 = (20*54 - 50* 6) /60 which is same as the weighted average application.
= (20*9 - 50)/10 =130/10 = 13 % profit
Option D is the answer.Thanks,
Clifin J Francis,
GMAT QUANT SME