The traffic lights at three different road crossings change after 24 seconds, 36 seconds and 54 seconds respectively. If they all change simultaneously at 10 : 15 : 00 AM, then at what time will they again change simultaneously? 

Two numbers are in the ratio 3: 4 if their LCM  is 240 then smaller number will be

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

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

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

Three men step off together from the same spot. Their steps measure 63 cm, 70 cm and 77 cm respectively. The minimum distance each should cover so that all can cover the distance in complete steps 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.