Find the sum of 30²+31²+32²+________+80²

The value of is closest to : 

The sum of three numbers is 252. If the first number is thrice the second and third number is two-third of the first, then the second number is

The difference between the average of squares of the last four numbers and the product of the first two numbers of 6 consecutive odd numbers is 114. Find the first number.

A number consists of two digits and the digit in the ten's place exceeds that in the unit's place by 5. If 5 times the sum of the digits be subtracted from the number, the digits of the number are reversed. Then the sum of the digits of the number is:

When 3738, 5659 and 9501 are divided by the greatest possible number x, the remainder in each case is y. What is the sum of x and y?

Sum of two numbers is 15 and sum of their reciprocals is . The two numbers are

If (x¹¹+1) is divided by (x+1), then the remainder is :