The price of 10 chairs is equal to that of 4 tables. The price of 15 chairs and 2 tables together is Rs. 4000. The total price of 12 chairs and 3 tables is:  Select the correct option
A) 3500 B) 3200 C) 3900 D) 3400 E) 3800
Let the cost of a chair and that of a table be Rs. x and Rs. y respectively.   Then, 10x = 4y or y = 5/2 x.   Therefore, 15x + 2y = 4000   =15x + 2 x 5/2x = 4000   =20x = 4000   Therefore, x = 200.   So, y =(5/2 x 200) = 500.   Hence, the cost of 12 chairs and 3 tables = 12x + 3y   = Rs. (2400 + 1500)   = Rs. 3900.   Answer is 3900.
<result>C</result>
The price of 10 chairs is equal to that of 4 tables. The price of 15 chairs and 2 tables together is Rs. 4000. The total price of 12 chairs and 3 tables is: