Answer:
$2,000
Explanation:
Since B sold the article to C at a gain of 20%, 2,640 must be 120% or 1.2 times the price that B paid.
To find the price that B paid, we just need to divide 2,640 by 1.2, as the original price multiplied by 1.2 = a 20% increase.
2,640/1.2= 2,200
The price B paid for it must have been 2,200.
Now we know that 2,200 was the price sold by A to gain 10%, therefore it is 110% or 1.1 times the original price A paid for it. Therefore, once again to find the original price, we just need to divide it by 1.1:
2,200/1.1 = 2,000
The original price it cost A was $2,000.
Hope this helped!