Makro Ekonomi - Keseimbangan Perekonomian 4 Sektor (Contoh Soal dan Pembahasannnya)

Introduction

This tutorial will guide you through the concepts of macroeconomics focusing on the equilibrium of a four-sector economy. You'll learn how to calculate national income and understand the relationships between consumption, taxes, imports, and exports. This is essential for students and anyone interested in understanding macroeconomic principles.

Step 1: Understanding the Four-Sector Economy

In a four-sector economy, we consider the following components:

• C: Consumption
• I: Investment
• G: Government Spending
• X: Exports
• M: Imports

Key Formulas

1. Consumption Function: [ C = 100 + 0.8Y_d ] Where (Y_d) is disposable income.

2. Tax Function: [ T = 0.25Y ]

3. Imports: [ M = 0.10Y ]

Step 2: Setting Up the National Income Equation

To find the equilibrium in the economy, we use the national income identity: [ Y = C + I + G + X - M ] Where:

• (Y) = National Income
• (C) = Consumption
• (I) = Investment (given as 200)
• (G) = Government Spending (given as 200)
• (X) = Exports (given as 400)
• (M) = Imports (depends on (Y))

Step 3: Calculating Disposable Income

Disposable income is calculated as: [ Y_d = Y - T ] Substituting the tax function: [ Y_d = Y - 0.25Y = 0.75Y ]

Step 4: Substitute and Solve for Equilibrium

1. Substitute (C) and (M) into the national income equation: [ Y = (100 + 0.8(0.75Y)) + 200 + 200 + 400 - (0.10Y) ]

2. Simplify the equation: [ Y = 100 + 0.6Y + 800 - 0.10Y ] [ Y = 900 + 0.50Y ]

3. Rearrange to isolate (Y): [ Y - 0.50Y = 900 ] [ 0.50Y = 900 ] [ Y = 1800 ]

Step 5: Analyzing Imports and Exports

Now, determine if imports exceed exports:

• Calculate imports: [ M = 0.10(1800) = 180 ]
• Exports are given as (X = 400).

Conclusion on Imports and Exports

Since (M (180) < X (400)), exports exceed imports.

Step 6: Adjusting Import Function

Next, consider the scenario where: [ M = 0.20Y ]

1. Substitute into the national income equation and repeat the steps to find the new equilibrium.
2. Check if exports will exceed imports under this new scenario.

Conclusion

In this tutorial, we covered how to analyze a four-sector economy and calculate national income at equilibrium. We determined that with the given values, exports exceed imports, and we discussed how changing the import function affects this equilibrium. For further study, consider varying the parameters and analyzing their impact on the economy.