Using graph, find the cost when quantity is 3 units.
Rs 5
Rs 6
Rs 8
Rs 4
Thus, from the above graph, the cost of 3 units is Rs 6.
Using graph, find the cost when quantity is 7 units.
The ratio of the cost of an item to its quantity is 2 :3 . If the cost of the item is ₹ 450, find the quantity