Quantitative Aptitude - Arithmetic Ability Questions

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

If cot A = n/(n + 1) and cot B = 1/(2n + 1), then what is the value of cot (A + B)?

If 1/(cosecA ­ cotA) = x, then the value of x is

If a - b = 1 and ab = 6, then what is the value of a3- b3?

Rs. 782 is divided into 3 parts in the ratio 12:23:34, the first part is 

Prahlad has done 1/3rd of a job in 30 days, Sarfaraz completes the rest of the job in 90 days. In how many days can they together do the job?

A man travelled a distance of 60 km in 7 hours. He travelled partly on foot @ 6 km/hr and partly on bicycle @ 12 km/hr. What is the distance (in kms) travelled on foot?

Sita told her friend Gita " I am leaving today and will reach Mumbai tomorrow for my exams starting the day after tomorrow, which is Friday". What day is tomorrow in this conversation?