Quantitative Aptitude - Arithmetic Ability Questions

If a+b+c=15 and 1a+1b+1c=71abc, then the a3+b3+c3-3abc is

Two pipes can fill a cistern in 28 and 21 hours respectively and an another pipe can empty 30 gallons of water per hour. All the three pipes working together can fill the empty cistern in 84 hours. What is the capacity (in gallons) of the cistern?

A person purchased 10 shirts costing Rs 150 per shirt. Next day  he again purchased the shirts costing Rs 150 per shirt at a discount of Rs 30 per shirt and that day he spent a toal of Rs 1800. What is the average cost per shirt (in Rs)?

13 years ago Ram was twice as old as Sunny. Three years from now Sunny's age will be 3/5 of Ram's age. What is Ram's current age?

The sum of digits of a two-digit number is 9. When the digits are reversed, the number decreases by 45. Find the changed number.

Select the odd word/letters/number/number pair from the given alternatives.

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

What is the value of Cot 45° - (1/√3)Cosec 60°?