If 0.4x + 0.3y = 2.3 and 2.5x - 2y = -5, then the value of xy is : 1. 10 2. 12 3. 2.4 4. 1.2

Given, 0.4x + 0.3y = 2.3 and 2.5x - 2y = -5 Solving first equation, ⇒ 0.4x + 0.3y = 2.3 ⇒ 10(0.4x + 0.3y = 2.3) [Multiplying both sides by 10] ⇒ 4x + 3y = 23 ⇒ 4x = 23 - 3y ⇒ x = ....(1) ⇒ 2.5x - 2y = -5 ....(2) Substituting value of x from equation (1) in 2.5x - 2y = -5, we get : Substituting value of y in equation (1), we get : x = 2 and y = 5. xy = 10. Hence, option 1 is the correct option.