Quantitative Aptitude - Arithmetic Ability Questions

If rsin∅ =1, rcos∅=√3, then the value of r2tan∅ is

Two numbers are 10% and 20% lesser than a third number respectively. By how much percent is the second number should be enhanced to make it equal to the first number?

If Mr. Raghav taught a total of 500 hours, then what is the difference in number of hours of teaching algebra and modern Maths?

A can make a cupboard in 10 days and B can do it in 50 days. Along with C, they did the job in 6.25 days only. Then in how many days C alone can do the job?

A pipe, working at full speed, can fill an empty cistern in 1 hour. However, during the first hour it worked at one-twelfth of its capacity, during the second hour at one-ninth of its capacity, during the third hour at one-sixth of its usual capacity and during the fifth hour it was only one -third as efficient as it was supposed to be. A second pipe also displayed similar performance, but if it worked at full speed would have filled the empty cistern in 2 hours. Together with a drain pipe that drained water out of the tank at a constant rate, the empty cistern could be filled in 5 hours, all the three pipes working concurrently. How many hours will it take the drain pipe to empty the filled cistern if no other pipe was functioning during the time?

In the following question, select the odd letter/letters from the given alternatives.

In a week, how many times are the hands of a clock at right angles with each other?

What is the value of Tan 45° + 4/√3 Sec 60°?