List of top Mathematics Questions on Playing with Numbers asked in CBSE Class VI

The traffic lights at three different road crossings change after every 48 seconds, 72 seconds and 108 seconds respectively. If they change simultaneously at 7 a.m., at what time will they change simultaneously again?

In which of the following expressions, prime factorisation has been done?

Write the smallest digit and the greatest digit in the blank space of each of the following numbers so that the number formed is divisible by 3 :
1.  __ 6724
2.  4765 __ 2

Which of the following numbers are prime?