Find the sum of all prime numbers between 10 and 90.

 The least number by which 448 is to be divided to make it a perfect cube is

The numbers 1, 3, 5, 7______99 and 128 are multiplied together. The number of zeros at the end of the product must be: 

Nathu and Buchku each have certain number of oranges. Nathu says to Buckhu, " If you give me 10 of your oranges, I will have twice the number of oranges left with you “. Buckhu replies, " If you give me 10 of your oranges, I will have the same number of oranges as left with you." What is the number of oranges with Nathu and Buckhu , respectively ?

The sum of 10 terms of the arithmetic series is 390. If the third term of the series is 19. Find the first term

How many even three-digit numbers can be formed from the digits 1 , 2 , 5 , 6 and 9 without repeating any of the digits? 

A number x when divided by 289 leaves 18 as the remainder. The same number when divided by 17 leaves y as a remainder. The value of y is 

Find the least number exactly divisible by 12,15,20,27 ?