Twenty-one time of a positive number is less than its square by 100. The value of the positive number is

If the 8-digit number 888x53y4 is divisible by 72, then what is the value of (7x + 2y) for the maximum value of y?

What is the average of the first 13 odd numbers?

The product of 1.7 ´ 10⁴ and 12.5 ´ 10^–6 is expressed in the standard form as k ´ 10ⁿ . The value of (2k + n) is

The product of 2 numbers is 1575 and their quotient is 9/7. Then the sum of the numbers is –

Direction: What value will come in place of the question mark (?) in the following question?

32, 50, 86, ?, 212, 302

The 4th term of an arithmetic progression is 15, 15th term is -29, find the 10th term?

1! + 2! + 3! + 4! + ......... + 50! Find the unit digit of?