Quantitative Aptitude - Arithmetic Ability Questions

Which of the following is correct?

What is the value of sec -2π/3 ?

Point A divides segment BC in the ratio 4:1. Co-ordinates of B are (6 , 1) and C are (7/2 , 6). What are the co-ordinates of point A?

A, B and C are employed to complete a work in Rs. 784. If A and B together complete 23/28 of the work. Calculate the wages (in Rs.) paid to C?

If 4r = h + r2+h2 then r: h = ? (r not equal to 0)

How many balls of radius 2 cm can be made by melting a bigger ball of diameter 16 cm? (Take π = 22/7)

Z’s present age is 55 years. If 11 years ago, C’s age was 1/11 of Z’s age, then after how many years C’s age will become 37 years?

If 20 men working 8 hours per day can complete a piece of work in 21 days. How many hours per day must 48 men work to complete the same job in 7 days?