Final Answer:
The individual should attend school if the present-discounted value (NPV) of the high earnings (wh) in period 1, discounted at the rate r, minus the cost of schooling (c) in period 0, is greater than the earnings without schooling (wl) in both periods.
Step-by-step explanation:
In order to maximize the present-discounted value of earnings, the individual needs to compare the NPV of attending school with the NPV of not attending school. The NPV of attending school is given by:
![\[ NPV_{\text{school}} = wh - c + (wh)/((1+r)) \]](https://img.qammunity.org/2024/formulas/business/high-school/6immkucara9d3sll92q55przj1j6zym098.png)
Here,
represents the earnings in period 1 after deducting the cost of schooling, and
represents the discounted value of those earnings in period 1. The NPV of not attending school is simply
, as the individual earns the low amount (wl) in both periods. Therefore, the decision rule is:
![\[ NPV_{\text{school}} > 2 * wl \]](https://img.qammunity.org/2024/formulas/business/high-school/bqggyfrfvwcdsmwqxfwect8pimlnfvdhuj.png)
Solving this inequality will provide the conditions under which attending school is optimal.
In conclusion, the individual should attend school if the NPV of the high earnings in period 1, discounted at rate r, minus the cost of schooling, is greater than the NPV of earnings without schooling. This decision is based on maximizing the present value of earnings over the two periods while accounting for the discounting factor.