Quantitative Aptitude - Arithmetic Ability Questions

Which number is 30% less than 80% of 800?

If 6A = 7B = 5C; find A : B : C

The interest earned on Rs. 1600 at the rate of 5% S>I per annum for 6 yrs would be:

The time taken by 4 men to complete a job is double the time taken by 5 children to complete the same job. Each man is twice as fast as a woman. How long will 12 men, 10 children and 8 women take to complete a job, given that a child would finish the job in 20 days.

A trader had 2000 kgs of rice. He sold a part of it at 10% profit and the rest at 16% profit, so that he made a total profit of 14.2%. How much rice (in kg) did he sell at 10% profit?

If Cosec θ = 17/8, then what is the value of Cos θ?

If x +y = √3 and x - y = √2, then the value of 8xy (x2 + y2) is

If the average age of 20 students in Class-I is 10 years and average age of 25 students in Class II is 12 years, find the average age (in years) of all students.