Question

Suppose the consumption function is c = $200 + 0.85yd. if disposable income is $400, consumption is

Answer 1

$540 is the answer in this question. The formula of level of consumption is equal to autonomous consumption plus the disposable income multiplied by the MPC; 
Disposal income = $400
MPC = .85YD
Autonomous consumption = $200

So the solution for this question is 

.85 × 400 + 200 = 540.

Answer 2

Given the consumption equation of c= 200 + 0.85yd, and the disposable income of $400, then, then we would get the consumption by substituting the given to the equation:c= 200 + 0.85ydc= 200 + 0.85(400)c= 200 + 340c= 540Therefore, the consumption is $540.