Quantitative Aptitude - Arithmetic Ability Questions

A student, by mistake, wrote 64 in place of 46 as a number at the time of finding the average of 10 given numbers & got the average as 50. The correct average of the numbers is

Two trains start moving from stations S and R. Both trains move towards each other at speeds of 35 km/hr and 42 km/hr respectively. When they meet each other, the second train has travelled 90 km more than the first. What is the distance (in km) between S and R?

Average age of 6 boys is 14 years. Average age of 11 girls is 12 years. What is the average age (in years) of all boys and girls?

A balloon leaves from a point P rises at a uniform speed. After 6 minutes, an observer situated at a distance of 450√3 metres from point P observes that angle of elevation of the balloon is 60 deg. Assume that point of observation and point P are on the same level. What is the speed (in m/s) of the balloon?

The ratio between the weights of gold and silver in an alloy is 17:3. If the weight of silver in the alloy is 2.7 gm, find the weight of gold in the alloy?

If secA/(secA ­- 1) + secA/(secA + 1) = x, then x is

If cos -4π/3 = x, then the value of x is

The factors of x2 + 8x + 12 are