Answer:
$500
Step-by-step explanation:
Money supply at original level = [ currency deposit ratio + 1]* B / [ currency deposit ratio + reserve deposit ratio]
currency deposit ratio = 1/2 = 0.5
reserve deposit ratio = 1/4 ( one quarter) = 0.25
Base ( B) = 2000
Money supply at original level = [ 0.5 + 1]*2000/ [0.5 + 0.25] = 4000
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To find the monetary base required to keep the money supply at its original level of $4000, substitute $4000 in the money supply equation and keep B variable
4000 = [new currency deposit ratio + 1]* B / [ new currency deposit ratio + reserve deposit ratio ]
4000 = [ 1+1]*B / [ 1+ 0.25]
4000 = 1.6B
B = 4000/1.6
B= 2500
Therefore the government should increase the monetary base by buying government bonds worth $500( = 2500-2000)