If total benefit is rising at the same rate that total cost is rising, the decision maker should maintain this level of activity since it is the optimal level

If total benefit is rising at the same rate that total cost is rising, the decision maker should maintain this level of activity since it is the optimal level.

Rise in total benefit implies marginal benefit. Similarly, rise in total cost implies marginal cost. When total benefit is rising at the same rate at which total cost is rising, it suggests that marginal benefit equals marginal cost.

The optimal decision point is that level when marginal benefit equals marginal cost. Such as, a producer produces the level of output at which marginal benefit equals marginal cost. It is so because if the producer produces lesser than this optimal level, he would loose the opportunity to earn more net benefit by producing more of the good. On the other hand, if he produces more than the level (where marginal benefit equals marginal cost) the net cost would be more, reducing the net benefit. Therefore, the level at which maximum returns occurs is the level at which marginal benefit equals marginal cost. That is why if total benefit is rising at the same rate that total cost is rising, the decision maker should maintain this level of activity since it is the optimal level.