Quantitative Aptitude - Arithmetic Ability Questions

Which one of the following is not a prime number?

Sharan and Mayukh, working together, can complete a task in 18 days. However, Mayukh works alone and leaves after completing 1/3 of the task. Then, Sharan takes over and completees the remaining work by himself. As a result, the duo could complete the task in 40 days. How many days would Sharan alone have taken to do the job if Mayuk' had worked faster than Sharan ?

Shamma lends Rs.40,000 to two of her friends. She gives Rs.24,000 to the first at 8% p.a. simple interest. Shamma wants to make a profit of 10% on the whole. The simple interest rate at which she should lend the remaining sum of money to the second friend is:

The effective annual rate of interest corresponding to nominal rate of 6% per annum payable half yearly is

Jeremy is 26 years younger than his father. Eight years hence his father's age will be two years less than twice his age. What is Jeremy's present age?

If two painters can complete two rooms in two hours, how many painters would it take to do 18 rooms in 6 hours?

A car runs at the speed of 50 kms per hour when not serviced and runs at 60 km./hr. when serviced. After servicing the car covers a certain distance in 6 hours. How much time will the car take to cover the same distance when not serviced?

Three triangles are marked out of a bigger triangle at the three vertices such that each side of each of the smaller triangles is one-third as long as each corresponding side of the bigger triangle. The ratio of the area of the three small triangles taken together to that of the rest of the bigger triangle is ?