Quantitative Aptitude - Arithmetic Ability Questions

If a + b = 10 and ab = 21, then the value of (a - b)2 is

If x + y = 12 and x2 + y2 = 94, then xy is 

Area of _____ equals square of its side.

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

Marked price of an item is Rs 900. On purchase of 2 items discount is 16%, on purchase of 5 items discount is 44%. Raksha buys 7 items, what is the effective discount?

The value of ds+t÷ds÷dt

The sum of a number and 4 times its reciprocal is 5. What is the number?

Among three numbers, the first is twice the second and thrice the third. If the average of three numbers is 396, then what is the difference between the first and the third number?