Question $28$

If an initial increase in government spending of $$100$ billion leads to a total increase of $$400$ billion in income, the marginal propensity to consume in the economy is:

$0\mathrm{.}4$

$0\mathrm{.}8$

$-0\mathrm{.}8$

$0\mathrm{.}75$

$0\mathrm{.}5$