Nếu có một sự giảm sút trong đầu tư của tư nhân 10tỷ MPC = 0,75 mức sản lượng sẽ:A. Giảm xuống 40tỷB. Tăng 40 tỷC. Giảm xuống 13,33tỷD. Tăng lên 13,33tỷ

Break Down the Problem

1. Identify Variables:

   • Decrease in private investment: $\Delta I = -10$ trillion.
   • Marginal Propensity to Consume (MPC): $MPC = 0.75$.

2. Determine the Multiplier:

   • The multiplier ($k$) can be calculated using the formula: $k = \frac{1}{1 - MPC}$

3. Calculate the Change in Output:

   • The change in output ($\Delta Y$) is given by: $\Delta Y = k \times \Delta I$

Relevant Concepts

1. The concept of the multiplier effect in economics states that an initial change in spending (in this case, a decrease in investment) will lead to a larger change in overall income or output.

Analysis and Detail

1. Calculate the Multiplier:

   • First, calculate the multiplier: $k = \frac{1}{1 - 0.75} = \frac{1}{0.25} = 4$

2. Calculate the Change in Output:

   • Now, use the multiplier to find the change in output: $\Delta Y = 4 \times (-10) = -40 \text{ trillion}$

Verify and Summarize

• The output decreases by 40 trillion. This implies that the new output level will fall to a value significantly below the previous level, indicating a contraction in the economy due to the decrease in private investment.

Final Answer

The level of output will decrease by 40 trillion. Therefore, the correct answer is: A. Giảm xuống 40 tỷ.