Final Answer:
The $1,800,000 injection into the money supply results in an overall increase of $7,200,000 in demand deposits.
Step-by-step explanation:
When Andrew deposits $1,800,000 into his checking account at Southeast Mutual Bank, the bank's liabilities increase by the same amount, reflecting the new demand deposit. The required reserve ratio is 25%, so Southeast Mutual Bank must hold $450,000 (25% of $1,800,000) as required reserves. The remaining $1,350,000 becomes excess reserves.
Now, as Southeast Mutual Bank loans out its excess reserves of $1,350,000 to Teresa, and this process continues through Walls Fergo Bank, PJMorton Bank, and finally to Eleanor, the total increase in demand deposits is the sum of the initial deposit and the subsequent loans. Each bank makes new loans equivalent to its excess reserves, and as these loans are deposited into other banks, they create additional demand deposits. The cumulative increase is calculated by multiplying the initial deposit by the money multiplier.
The money multiplier is the reciprocal of the reserve requirement ratio. In this case, the reserve requirement ratio is 25%, so the money multiplier is 1/0.25, which equals 4. Therefore, the overall increase in demand deposits is $1,800,000 (initial deposit) multiplied by 4, resulting in $7,200,000.
In summary, the initial deposit sets off a chain reaction of loans and deposits through the banking system, leading to a total increase in demand deposits of $7,200,000. This process is guided by the reserve requirement ratio and the money multiplier, reflecting the impact of the initial deposit on the overall money supply.