Quantitative Aptitude - Arithmetic Ability Questions

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

Which of the following numbers will have an irrational square root?

A man travels 50 km at speed 25 km/h and next 40 km at 20 km/h and there after travel 90km at 15 km/h. His average speed is

A solid sphere of diameter 7 cm is cut into two equal halves. What will be the increase (in cm2) in the total surface area ?

In how many years will Rs 2,000 yield Rs 662 as compound interest at 10% per annum compounded annually?

If πsinθ= 1, πcosθ= 1, then (3tan 23θ+1) is

What is the unit digit of 15+25+35+...+205 ?

Two water-squash mixtures, the first having a water-to-squash ratio of 4 : 1 and the other having a ratio of 3 : 1, are blended in the ratio 1 : 2. What is the water : squash ratio in the blend?