JNU 2010

[neha:)]

Q. 57. Suppose a plant can be used to produce in a day x units of product 1 and y units of product 2 where
y = (32-5x)/(10-x) where x lies in [0, 32/5]. If the unit price of product 1 is twice the unit price of product 2, then to maximize total revenue the number of units of x the  plant should be used to produce in a day is
a). 4
b). 5
c). 6
d). 6.4

[ViV]

Px = 2Py. Let, Py = 1 and Px = 2
Now play with the options.
x=4, y= 32-20/6=2
TR(x) = p.x = 2*4 = 8, TR(x)= Total Revenue by producing x commodity
TR(y) = p.y = 1*2 = 2
Like this find the TR(x) at all x =5,6,6.4
you will find TR(x) at x =6.4 is 12.8 which is maximum then another value of x.
Hence, (d) is the answer

[kangkan]

or you can equate TRS= price ratio..same ans though :)

[Granpa Simpson]

[neha:)]

Thanks everyone!