Quantitative Aptitude - Arithmetic Ability Questions

Shivam is 10% less efficient than Vivek. If Vivek can make a helmet in 9 days, then in how many days Shivam can complete the same work?

A and B can complete a task in 20 days, B and C can complete it in 30 days while C and A can do the same task together in 24 days. How many days will each of and C take to complete the task individually? 

The average of 5 consecutive numbers is 50%, then difference between 'product of largest and smallest number' with 'product of fourth and second number' is

Instead of multiplying by 25, a student multiplies that number by 52 and gets 324 more than correct answer. Then that number is

If "basis points" are defined so that 1 percent is equal to 100 basis points, then by how many basis points is 82.5 percent greater than 62.5 percent?

The angle of elevation of the top of a tower from a point A on the ground is 30°. On moving a distance of 20 metres towards the foot of the tower to a point B, the angle of elevation increases to 60°. The height of the tower in meters is

What is the third proportional to 10 and 25?