Answer: Increase by $250
Explanation: As per the general rule of economics when there is an increase in income, that increase will eventually lead to increase in expenditure.
As, there is an increase in investment in the given case so it will result in increase in income for the economy.
We can compute it as :-
![change\:in\:income=(change\:in\:investment)/(1-MPC)](https://img.qammunity.org/2020/formulas/business/high-school/yj5fhnkaghj9kwooprlbnirmybnzot8jr6.png)
![change\:in\:income=(\$50)/(1-0.8)](https://img.qammunity.org/2020/formulas/business/high-school/mjnaqoocnii5z4zyyn13e9w8ci79ds1enh.png)
= $250
Therefore, the expenditure would increase by $250