Quantitative Aptitude - Arithmetic Ability Questions

Determine the value of  'a' which satisfies the equation 9a + 40a = 41a

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

A bookseller bought 500 text books for  20,000. He wanted to sell them at a profit so that he get 50 books free. At what profit percent should he sell them?

Cost price of a calculator is Rs 495. If the profit percentage is 40%, then what is the value (in Rs) of profit?

When a discount of 20% is given on a lunch buffet, the profit is 42%. If the discount is 15%, then the profit is

If a vendor sells a coconut at Rs 24 he makes 20% loss. If he sells at Rs 36 then what is his profit percentage?

X can complete 5/7 part of a work in 10 days and Y can complete 3/4 part of the same work in 9 days. In how many days will both complete 13/21 part  of the total work?

The sum of a non-zero number and 4 times its reciprocal is 17/2. What is the number?