There is another method to solve this, and that is alligation
CarA CarB
+10% -10%
5%
----------------------------
15% : 5%
3 : 1
5% = 1000, Therefore cost price will be 20,000
15000 and 5000 are the only two options solving upon which we can get the right answer as 1000 profit
Bunuel
A car dealership sold two cars: Car A at a 10% profit and Car B at a 10% loss, resulting into an overall profit of 5% from the two sales. If the dealership's profit from these two cars was $1,000, what was the initial cost of cars A and B?
A. $5,000 and $1,000
B. $9,000 and $5,000
C. $11,000 and $9,000
D. $15,000 and $5,000
E. $20,000 and $10,000