Directions : The Bar Graph given here shows the population (in crores) of India in various census years. Observe the graph and answer the question based on it.

The per cent increase in population from 1971 to 1981 is

if $${secθ={a\over b},b≠0,then \ {{1-tan^2θ}\over 2-sin^2θ}  }=?$$

12 persons can do a piece of work in 4 days. How many persons are required to complete 8 times the work in half the time?

Find the area of the triangle whose sides are 5 cm, 12 cm and 13 cm.

Directions: The following pie chart show proportion of population of seven villages in 2009. Stud the pie chart and answer question that follows:

If the below poverty line population of the village 'X' is 12160, then the population of village 'S' is 

Directions: The following Pie Chart shows the export of different food grains from India in 2010. Study the chart and answer the questions:

If a total of 1.5 million quintals of crop F was exported, then the total quantity of D and E that was exported (in million quintals) was

if $${{x^{24}+1}\over x^{12}}=7$$ then the value of   $${{x^{72}+1}\over x^{36}}$$ is

A solid metallic sphere of radius 12 cm is melted and recast into a cone having diameter of the base as 12 cm. What is the height of the cone?