Quantitative Aptitude - Arithmetic Ability Questions

If x+y+z = 1, 1/x + 1/y + 1/z = 1 and xyz = -1, then x3+y3+z3 is equal to

What should be the average speed of a car to cover a distance of 189 km in 3.5 hours?

Bhanu takes a total of 6 hrs 50 min in walking a distance and running back to same place where she started. She could walk both ways in 8 hrs 30 min. The time taken by her to run both ways is :

Reflection of the point (2,-4) in the origin is

What is the value of (cos 40° – cos 140°)/(sin 80° + sin 20°)?

If x + y = 10 and x2 + y2 = 68, then find xy

A person clapped his hands near a cliff and heard echo after 6 s. The distance of the cliff from the personis: [take v = 346 m/s]

A car travels a certain distance at 70 km/h and comes back at 30 km/h. Find the average speed for total journey.