Question

Rohit bought 20 oranges and 30 bananas for Rs. 280. If the cost of each orange had got doubled, then he would have bought 30 oranges and 40 bananas for Rs.540. Find the original cost of each orange

Answer 1

Let cost of each orange = Rs. x
     cost of each banana = Rs. y
Cost of 20 oranges and 30 bananas = 20x+30y
So 20x+30y = 280
⇒ 2x + 3y = 28

if cost of each orange is doubles, cost of each orange = 2x
cost of 30 oranges and 40 bananas = 30(2x) + 40y  = 60x+40y
thus 60x+40y = 540
⇒6x + 4y = 54

Solving the two equations we get, x = 5 and y = 6.
 So cost of each orange = Rs. 5.