40 men were employed in a farm, and they produced an average of 30 tonnes of cassava per person. Calculate the total product.

Analyze the question: You are given the number of workers (40) and the average product per worker (30 tonnes). You are asked for the total product.

Concept: Average product (AP) is the output per unit of the variable factor (here, labour):

AP = Total Product (TP) ÷ Number of workers (L)

Rearranging:

TP = AP × L

Solution:

• Number of workers, L = 40
• Average product, AP = 30 tonnes per person

TP = 30 × 40 = 1,200 tonnes

Answer: Option C, 1,200 tonnes.

Tip: When a question gives an "average" and a "number of units", just multiply to get the total. If it gives the total and the number of units, divide to get the average. Remember the triangle: TP on top, AP and L at the bottom. Cover what you want to find and the formula appears.