You are given the following data for national economy of

Solution

A 5% increase in GDP which is currently $6,000,000,000 would be $300,000,000. A 5% increase in GDP would require less than a 5% increase in spending due to the multiplier effect. Every dollar of government spending will be spent and re-spent in the circular flow of economic activity. For example, if road construction is authorized, government spending for materials and workers will be spent again by the materials suppliers and the hired workers. Thus, the boost to the economy will be more than 5%. If the MPC (Marginal Propensity to Consume) is .8, then the MPS (Marginal Propensity to Save) must be .2, because together the percentages must add up to 1. Thus, the spending multiplier is 1 / (1 - MPC). In this example, it would be 1 / .2 or 5. That means that each dollar of government spending will generate 5 times that much GDP. To increase GDP by $300,000,000, therefore would take an increase of $300,000,000/5 or $60 million.