Quantitative Aptitude - Arithmetic Ability Questions

Which of the following is not a quadratic equation?

If cot(A/2) = x, then x is equal to

An article was sold at Rs. 950 allowing 5% discount on the marked price. The marked price of the article is

Find the odd word/letters/number from the given alternatives

On Selling a toy at 20/31 of the marked price there is a loss of 20%. What will be the ratio of marked price and cost price of the toy?

If (4/5)A = 3B = (2/3)C, then what is A : B : C?

If the shopkeeper sells an item at Rs 4400 which is marked as Rs 5000, then what is the discount that he is offering?

If a certain sum of money doubles itself in 7 years 8 months at simple interest, then what will be the yearly rate of interest (in %)?