Determine the aggregate expenditure curve (equation) at given the variables.

1. Compute for the equilibrium aggregate real income Y and multiplier effect in the economy.
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3. Suppose the autonomous investment spending decreases twenty percent or 43 units from 215 to 172, while the other variables are assumed to be constant. Using the multiplier effect, calculate the new equilibrium aggregate real income Y.
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5. Determine the new aggregate expenditure curve at the new autonomous investment spending level of 172. Assume that the variables are constant.
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7. Compute for the new equilibrium aggregate real income Y using the new aggregate expenditure curve and multiplier effect in the economy.

The variables in the model for the aggregate expenditures in an economy are: Co = 240, lo = 215, Go = 135, Xo = 115, Mo = 90, Tp = 40, C = 0.75, i = 0.15, and m = 0.20. Note that disposable income is gross income minus personal tax: Yp=Y - Tp. Aggregate expenditure is equal to sum of the autonomous spending in each sector plus the spending induced by disposable income: E=Co+c(Y-Tp) + lo+iY+ Go +Xo-Mo-mY = Co-CTp + Io + Go + Xo - Mo + (C+i-m)Y