By which number should be multiplied so that the product is the reciprocal of ?

Find the smallest number which when increased by 20 is completely divisible by 12, 20, 15, 18 and 24.

The LCM of the numbers 3.7 and 0.068 is:

The number of prime numbers lying between 323 and 332 is:

The number of prime numbers lying between 300 and 305 is:

Find the Highest Common Factor (HCF) of 372, 732 and 2196.

What is the year before 2001 whose calendar is the same as 2001?