What is the LCM (least common multiple) of 57 and   93?

What is the L.C.M of 12, 23, 24?

Two numbers are in the ratio 3 : 4. Their L.C.M. is 84. The greater number is 

Two pipes of length 36 metre and 40 metre are to be cut into equal pieces without leaving any extra length of pipe. Find the number of such pieces if pipes are to be cut of maximum length.

Four bells ring at the intervals of 5, 6, 8, and 9 seconds. All the bells ring simultaneously at the same time. They will again ring simultaneously after: 

The LCM of three different numbers is 120. Which of the following cannot be their HCF? 

The least number, which is a perfect square and is divisible by each of the numbers 16, 20 and 24 is 

The least number, which when divided by 4, 5 and 6 leaves remainder 1, 2 and 3 respectively is: