Final answer:
The level of private investment in an economy can be calculated by adding private savings, government budget surplus, and trade surplus. In a steady state, investment equals savings, thus in this case, the private investment would be 900.
Step-by-step explanation:
Understanding Private Investment in an Economy
To determine the level of private investment in an economy, we need to consider private savings, government budget surplus, and the trade surplus. Given that private savings amount to 600, the government budget surplus equals 200, and the trade surplus is 100, we can use the formula for national savings to establish the level of private investment.
National savings are the sum of private savings, the government budget surplus, and the trade surplus. Therefore, the national savings in this economy would be 600 (private savings) + 200 (government budget surplus) + 100 (trade surplus) = 900.
In a steady state, investment equals savings. Hence, the level of private investment in this economy would be the same as the national savings, which is 900.