Answer:
Option (a) is correct.
Step-by-step explanation:
U(x1, x2) = x1x2
Income = 100 dollars
Therefore,
Alex budget constraint is $100.
(a) (12.5, 12.5)
Cost of this bundle = 12.5 × $4 + 12.5 × $4
= $50 + $50
= $100
(b) (25, 12.5)
Cost of this bundle = 15 × $4 + 10 × $5 + 12.5 × $4
= $60 + $50 + $50
= $160
This bundle is not possible because of budget constraint.
(c) (12.5, 25)
Cost of this bundle = 12.5 × $4 + 25 × $4
= $50 + $100
= $150
This bundle is not possible because of budget constraint.
(d) (15, 10)
Cost of this bundle = 15 × $4 + 10 × $4
= $60 + $40
= $100
Hence, it is possible to buy bundle (a) and (d).
Utility function for (a) and (d) bundle:
(a) (12.5, 12.5)
Utility = 12.5 × 12.5
= 156.25
(d) (15, 10)
Utility = 15 × 10
= 150
Therefore,
Alex will choose bundle (a) (12.5, 12.5) because this will give maximum utility.