The smallest even prime number is:

LCM of 15, 30 is:

Ravi wrote two digits of a 3- digit number on the black board as shown below.

And the missing digit is ______ if the number has 11 and 13 as factors?

21 and 31 are _________ numbers.

From the given data the number of prime numbers between 20 and 30 is:

Find the sum of first three multiples of 5.

Number of multiples of 9, which is less than 50?

_________ should subtracted from 642 to make it divisible by 8.

The sum of prime numbers between 20 and 30 is:

Find a number which is a multiple of all the numbers from 1 to 10?