In a small, closed economy, national income (GDP) is $ 400.00 million for the current quarter. Individuals have spent $ 150.00 million on the consumption of goods and services. They have paid a total of $ 200.00 million in taxes, and the government has spent $ 150.00 million on goods and services this quarter. Use this information and the national income identity to answer the questions. How much is spent on investment in this economy?

Investment (I) = business investment plus residential investment plus inventory investment. Government Purchases (G) = general government consumption plus general government investment. Net Exports (NE) = exports minus imports plus net tourism.

∴ to calculate the amount of money spent on this closed economy, I will use the Expenditure Approach formula for GDP and make Investment the subject of the formula which is

GDP formula is used which states that total output/GDP (Y) is equal to Consumption (C) + Investment (I) + Government Spending (G) + Net exports (NX). Where net exports is exports (X) minus imports (M): NX = X – M.

Where:

GDP (Y) = C + I + G + (X-M)

Where:

GDP (Y) = $400,000,000.00

C = $150,000,000.00

I = 0

G = $150,000,000.00

(X-M) = 0

GDP (Y) = C + I + G + (X-M) =

$400,000,000.00 = $150,000,000.00 + (I) + 150,000,000.00 + (X-M)

Making (I) the subject of the Formula

GDP- C -G = I

∴ $400,000,000.00 - $150,000,000.00 - $150,000,000.00 = I

∴ $400,000,000.00 - $300,000,000.00

= $100,000,000.00

The amount spent in this economy in the said quarter

= $100,000,000.00.

Note: I did not add the Tax because I used the Expenditure approach method which does not include the tax values while the Income Approach method does include it but excludes Export and Import values.