Let a consumer's marginal propensity to consume be 0.4.  The current CPI is 150, and the future CPI is 180.  The nominal interest rate is 50%.  The consumer receives a current tax cut of  70 dollars, and expects to receive a future tax increase of 40 dollars.  By what dollar amount does the consumer's saving change?  (Give an increase as a positive, and a decrease as a negative number.)

求助如何计算

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