Quantitative Aptitude - Arithmetic Ability Questions

The reciprocal of the sum of the reciprocals of 3/8 and 8/11 is:

A person driving at the speed of 40 kmph reaches office 1 minute early while he reaches 3 minutes late if driving at 36 kmph. What is the distance in km that she is covering?

B is thrice as efficient as A and C is 0.75 times as efficient as A. What is the ratio of number of days taken by A, B and C when they work individually?

ΔXYZ is right angled at Y. If cosX = 3/5, then what is the value of cosecZ ?

Find the value of x if 1-x24 = 1318

In a bag the ratio of red balls to green balls is 4 : 9. If 6 more green balls were added to the bag, the ratio of red balls to green balls would become 1 : 3. How many red balls are there in the bag?

If the value of √42 is approximately 6.480, then what is the approximate value of √(6/7)?

If the shopkeeper sells an item at Rs 4400 which is marked as Rs 5000, then what is the discount that he is offering?