If total cost of producing 7^th and 8^th unit of goods are Rs. 624 and Rs. 727 respectively, find marginal cost of producing 8^th unit of goods.

The marginal cost (MC) of producing the $8^{\text{th}}$ unit is calculated as the difference between the total cost (TC) of producing $8$ units and the total cost of producing $7$ units.

Given:

• Total cost of $7^{\text{th}}$ unit = Rs. 624
• Total cost of $8^{\text{th}}$ unit = Rs. 727

Step 1: Identify the total costs $${\text{TC}}_7=624,{\text{TC}}_8=727$$

Step 2: Apply the marginal cost formula $${\text{MC}}_8={\text{TC}}_8-{\text{TC}}_7$$

Step 3: Substitute the values $${\text{MC}}_8=727-624=103$$

Marginal cost of producing the $8^{\text{th}}$ unit of goods is Rs. 103.