In a simple, closed economy (no government and no foreign sector), autonomous consumer spending is $100, and planned investment spending is $300. The marginal propensity to consume is 0.75. What is the equilibrium level of real GDP

See the explanation Section

Explanation:

Every day I have to go to the market to purchase day to day utensils. Recently I witnessed a severe incident there. Before the incident day, I bought two pounds of onion with forty BDT. After the very next day, the price increased to 100. That happened due to the syndicate of businessmen and agents. However, it is challenging for the general people to take immediate action against them. That incident occurred due to the crisis of onions around the market. Moreover, there was little import from the neighboring countries.