Quantitative Aptitude - Arithmetic Ability Questions

The length of one side of a rhombus is 17 cm and one of the diagonals was 16 cm. Find the length of the other diagonal.

Which of the following quadratic equations has real roots?

What is the reflection of the point (5 , -1) in the line y = 2?

What is the reflection of the point (1 , 2) in the line y = 3?

Two trains are moving in opposite directions with the same speed. If the length of each train is 120 metres and they cross each other in 12 seconds, then what is the speed (in km/hr) of each train?

The ratio of present ages of Rangana and Sayed is 7:5. After 11 years the ratio of their ages will be 4:3. What is Rangana's present age?

cos(A+B) + cos(A-B) is equal to

A, B and C can complete a task together in 10 days. A and B would need 12 days if only the two of them worked, while B and C would take 20 days if only the two of them worked. If B worked alone, how many days would she take to complete the task?