JNU ECOM 2011 QUES 47-56

[Arushi :))]

QUES 47
If the marginal cost of producing 4th unit is greater than the marginal cost of producing 3rd unit, then it follows that:
a) the average cost of producing 4 units must be greater than the average cost of producing 3 units
b) the average cost of producing 4 units must be less than the average cost of producing 3 units
c) the average cost of producing 4 units must be equal to the average cost of producing 3 units
d) None of the above
Answer-d
QUES 48

Answer-d
QUES 49

Answer-
QUES 50

Answer-c
QUES 51
Suppose the price elasticity of demand for good X is 0.2 If the price of X rises by 2.8%, what effect will it have on the total expenditure on good X?
a) Expenditure on X will fall by 5.6%
b) Expenditure on X will rise by 5.6%
c) Expenditure on X will rise by 2.2%
d) Expenditure on X will fall by 2.2%
Answer-c
QUES 52

Answer-c
QUES 53
The probability distribution of a random variable X is given in the table below:

The mean and variance of X are respectively:
a) 2;2
b) 2; 1.4142
c) 1.37; 1.2731
d) None of the above
Answer-c
QUES 54
In a certain country telephone numbers have 8 digits. The first two digits are the area code and are the same within a given area. The last 6 digits are the local number and cannot begin with 0. How many different telephone numbers are possible within a given area code in this country?
a) (10)^6
b) 9^6
c) 900000
d) None of the above
Answer-c
QUES 55

Answer-d
QUES 56

Answer-b

[Arushi :))]

Any idea about 49??

[RajEco]

49. Option 2 is better than Option 1.

Consider the future values-
Option 1- 112
Option 2- 56 + 55*(1.03) = 112.65

[SoniaKapoor]

I think option a is better..
option 1:Future value=112*1.12=125.44
option 2:Future value=55*(1.12)^9/12 + 56*1.12=122.59

[Arushi :))]

For investments arent present values to be compared?

[Anjali]

Explanation for ques 47 ?

[Anjali]

For question 49 , option 2 is better
Take option 1 - Rs 112 , and calculate principal amount by SI formula .
P = 100
Come to the second option ,
SI for 9 months = 100 * .12 * 9/12 = 9
So after 9 months you get 109 amount. However you have received just 55 and have kept Rs 54 ( 109-55=54 ) in the bank. So calculate SI for 3 months = 54* 12/100*3/12 = 1.62
So in total you should get , 54+1.62 , but you are getting 56 . So this option is more feasible.

[Arushi :))]

@ anjali
for 47

I have made two situations where MC of 4th unit is greater than MC of 3rd unit.
But in the first situation
AC of 4 units < AC of 3 units.
In the second situation ( after the minimum point of AC curve)
both the situations are possible,
They could be equal, or AC of 4 units > AC of 3 units depending on how exactly is the AC curve
So no conclusion can be made.
Hence, i chose d.

[Anjali]

Okay so you mean that since we do not know the minimum point , we can make no conclusion . Is that so ?

[Arushi :))]

yes , because we just know that we are on upward sloping portion of MC curve.
We don't have any knowledge about min point of AC curve . And thus we can't say anything about Average costs.

[Ridhika]

So Im getting the same answer as you Raj, but this link has Amit sir's answer key for the paper.. and it says (d) for some reason.. No idea why..

Link:
http://discussion-forum.2150183.n2.nabble.com/JNU-2011-Answer-Key-td7563304.html#a7566480

[suvidya patel]

plz reply qno.51 and 54

[suvidya patel]

qno 56-a

[Noel]

For question 49 option 2 is better than option 1 but that can only be verified by a scientific calculator because for finding the future value/present value of 55,the quarterly interest rate q,must be calculated as follows
(1+q/4)^4=1.12
which gives q=11.494% approx.
so unless a scientific calculator is allowed we can't arrive at a conclusion..hence option d

[ViV]

49 (d) because there is no info regarding whether he is investing Rs. 55 for 3 months or not.
51 (b) or (c) because elasticity<1 (Inelastic) but I don't know the Exact number 2.2% or 5.6%

[The Villain]

Naah naah quest 49 is b for sure...

[jack]

Q.51
ed=.2
change in Q=(-.56)
TR=P.Q
take log both side
logTR=logp+logQ
total differentiate
so, total expenditure=change in P+ change in Q
                             =2.8+(-.56)
                             =2.2