Prepare the market demand schedule from the given demands of individuals. (Assuming that there are only three individuals X,Y and Z in the market)
`{:("Price Rs. Demand (X) Demand (Y) Demand (Z)"),(" 4 10 5 4"),(" 5 8 4 3"),(" 6 6 3 2"),(" 7 4 2 1"):}`

Explanation

`{:("Price Rs. Demand (X) Demand (Y) Demand (Z) Market Demand (X + y + Z)"),(" 4 10 5 4 19"),(" 5 8 4 3 15"),(" 6 6 3 2 11"),(" 7 4 2 1 7"):}`.