Quantitative Aptitude - Arithmetic Ability Questions

In a triangle XYZ , which of the following conditions is true

The difference between the compound interest compounding half yearly for 1 year and the simple interest for 1 year on a certain sum of money lent out at 8% per annum is Rs 64. What is the sum (in Rs)?

The ratio of two numbers is 3 : 7. If their product is 1344, then what is the sum of both the numbers?

Akka can bake 100 cakes in 20 hours, Akka and Tai together can bake 75 cakes in 10 hours. How many cakes Tai can bake in 20 hours?

10 people can build a wall in 12 days. Six people, each only half as efficient as those in the first group, will be able to complete 3/5 of such a wall in

A and B are 15 kms apart and when travelling towards each other meet after half an hour whereas they meet two and a half hours later if they travel in the same direction. The faster of the two travels at the speed of

P, Q and R together can make a table in 40 minutes. P and Q together can make it in 60 minutes. How much time (in minutes) will R alone take to make the table?

If x + (1/x) = 2, then what is the value of x64 + x121?