In: Economics
Brianna’s preferences can be
represented by the utility function u(x,y) = min{x,y}.
Initially she faces prices ($2,$1) and her income is $12. If prices
change to ($3,$1) then the compensating variation
Answer: The solution to the above problem can be derived as follows:
The given utility function U(x,y) = min{x,y}, implies perfect competency, which in turn implies that x = y.
Compensating Variation: The amount of money to give to the consumer to completely offset the price change
Now given the budget equation and the initial prices of the products, the budget equation is:
2x + 1y = 12
Since, x = y, we replace y with x in the budget equation and hence I get
2x + 1x = 12
or, x = 4 = y (as x=y)
So the utility function becomes U = min(4,4)
or, U = 4
Now after the price change the total expence becomes M = 4*3 + 4*1 (putting values of x and y and their new prices)
M = 16
So the compensating variation is 16 - 12 = 4
Equivalent Variation: The amount of money taken away from consumer that reduces his/her utility by increasing the price
After the price change the budget is
12 = 3x + 1y
or, 12 = 4x (replacing y with x)
or, x = 3 = y
So the utility becomes U = min(3,3) = 3
To have this utilty before the price chnage, the budget would be before price change
M = 3*2 + 1*2 = 8
So the Equivalent variation is 12 - 8 = 4
Hence we see that the Compensating variation is equal to Equivalent variation. Hence the correct answer is option d