Quantitative Aptitude - Arithmetic Ability Questions

Which of the following quadratic equations has real roots?

In the following question, select the odd letter from the given alternatives.

A shopkeeper offers 15% discount on all plastic toys. He offers a further discount of 4% on the reduced price to those customers who pay cash. What does a customer have to pay (in Rs) in case for a toy of Rs 200?

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?

Find the greatest number which on dividing 1580 and 3800 leaves remainders 8 and 1 respectively.

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?