If the length of a shadow of a pole on a level ground is twice the length of that pole, the angle of elevation of the sun is:-

The ratio of inradius and circumradius of an equilateral triangle is:

P and Q together can do a job in 6 days. Q and R can finish the same job in 60/7 days. P started the work and worked for 3 days. Q and R continued for 6 days to finish the work. Then the difference of days in which R and P can complete the job alone is 

What will be the compound interest on a sum of Rs. 21000 for 2 years at the rate of 14.28% per annum when interest is compound yearly?

Directions: Read the following table and answer the questions below it:

What was the percentage increase of disbursement of loans of all banks together from 1997 to 1998? 

A passenger train leaves Calcutta at 4 PM and travels at the rate of 30 kilometres an hour. The mail train leaves Calcutta at 9 PM and travels, on a parallel line of rails, at the rate of 45 km an hour, when will the second train overtake the first?

Study the information carefully to answer the question that follow.
In a college there are 900 students who are doing Post Graduation (PG) in any one of the subjects, out of five different subjects, out of the five different subjects viz. Zoology, Botany, Mathematics, Physics and Statistics. The ratio between the boys and the girls among those is 5:4 respectively, 20% of the total girls are doing PG in Zoology and 25% of the total girls are doing PG in Statistics. Total number of students doing PG in Botany is 220. Total students who are doing PG in Mathematics is 150. Respectively ratio between the number of girls and the number of boys doing PG in statistics is 2:3. Twenty percent of the total number of boys are doing PG in Mathematics is 1:2 respectively. There are equal number of boys and girls who are doing PG in PG in Physics. 180 students are doing PG in Zoology.
What is the difference between the boys doing PG in Zoology and the number of girls doing PG in Mathematics?