U 3X Y Px 6 Py 3 I 60 How much of X and Y should you buyS

U = 3X + Y; Px= 6; Py= 3; I = 60. How much of X and Y should you buy?

U = 3X+Y

I = 60

I = Px X + Py Y

60 = 6X + 3Y

20 = 2X+Y ------------------------------eq1

Now

MRS = Y/X = Px / Py

Y/X = 6/3

Y = 2X

2X-Y = 0 -------------------------------------eq2

Solve eq1 and eq2

So we get

X = 5 units

Y = 10 units

So he should 5 and 10 units of X and Y