Explanation

The price of 10 chairs = The price of 4 tables

Concept:

Linear equation of two variable = A equation is said to be linear equation in two variable if it is written in the form of ax + by + c = 0 Where, x and y are variables and a, b, and c are the integers

Calculation:

Let us assume the cost price of a chair be X and cost price of a table be Y

⇒ According to the question

⇒ 10X = 4Y ----(1)

⇒ 15X + 2Y = 4000 ----(2)

⇒ By equation (1) and (2)

⇒ 15X + 5X = 4000

⇒ X = 200 and Y = 500

⇒ The price of 12 chairs and 3 tables = (12 × 200) + (500 × 3) = 2400 + 1500 = 3900

∴ The required result will be 3900.