Quantitative Aptitude - Arithmetic Ability Questions

Identify the odd one out from the following:

Two fractions are such that their product is ­2/5 and sum is 1/15. What are the two fractions.

What is the value of cos 4π/3?

A 600 metres long train is running at the speed of 81 km/hr. If it crosses a platform in 40 seconds, then what is the length of the platform (in metres)?

∆DEF is right angled at E. If tanD = 4/3, then what is the value of tanF ?

The average revenues of 13 consecutive years of a company is Rs 78 lakhs. If the average of first 7 years is Rs 73 lakhs and that of last 7 years is Rs 85 lakhs, what is the revenue for the 7th year?

What is the HCF (highest common factor) of 77 and 275?

A thief is stopped by a policeman from a distance of 350 metres. When the policeman starts the chase, the thief also starts running. Assuming the speed of the thief as 7 km/h and that of police man as 12 km/h, how far the thief would have run, before he is over taken?