When the average product of a variable factor is rising as more units are employed, the marginal product is:

1. The AP-MP relationship has three rules tied to whether AP is rising, at its peak, or falling. 2. When AP rises, MP must lie above AP, pulling the average up. 3. So MP is greater than AP. 4. MP equals AP only at AP's maximum, MP is below AP only when AP falls, and a negative MP belongs to the stage of negative returns, not to rising AP. _Source: ICAI BoS CA Foundation Paper 4 Business Economics, Ch 3 Unit I "Theory of Production", p.17_