Quantitative Aptitude - Arithmetic Ability Questions

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

The sum of two positive integers is 80 & difference between them is 20. Then what is difference of squares of those numbers ?

Which of the following conditions is TRUE for the two line segments AB and CD to be congruent?

If a + b = 5 and ab = 6, then what is the value of a3 + b3?

The average of three numbers is 40. First number is 4/3 of the third number. If third number is 20 less than second number, then what is the value of second number?

The difference between compound interest and simple interest on Rs. 5000 for 2 years at 8% per annum payable yearly is

A 145 m long train crosses a 655 m long bridge in 36 seconds. What is the speed of the train?

A 800 metres long train is running at the speed of 90 km/hr. If it crosses a bridge in 50 seconds, then what is the length (in metres) of the bridge?