Measures of Dispersion — Economics STD 11 Commerce — Question

State some important demerits of standard deviation.

Give an example of a series which has two modes. What is the name given to such a series?

Locate the mode graphically:

Marks	0-10	10-20	20-30	30-40	40-50	50-60	60-70
No. of Students	5	10	20	25	20	10	5

The following news was printed in the Economic Times:
"Narrow petrol-diesel price gap and higher price of diesel cars alter buyer's preferences."
Explain this statement linking it to the concept of elasticity of demand.

Complete the following table:

Output (Units)	Total Cost (₹)	Average Variable Cost (₹)	Marginal Cost (₹)
0	60	-	-
1	140	-	-
2	190	-	-
3	240	-	-
4	300	-	-

A consumer spends ₹400 on a good priced at ₹8 per unit. When its price rises by 25 per cent, the consumer spends₹500 on the good. Calculate the price elasticity of demand by the percentage method.

Explain how price is determined in a perfectly competitive market with fixed number of firms.

A consumer spends ₹60 on a good priced at ₹5 per unit. When price falls by 20 per cent, the consumer continues to spend ₹60 on the good. Calculate price elasticity of demand by percentage method.

Complete the following table:

Output (Units)	Total Revenue (₹)	Total Cost (₹)	Profit (₹)
1	6	8	-
2	-	9	- 1
3	10	-	0
4	12	11	-
5	14	8	-