There are 100 blocks in a colony numbering 1 to 100.
A school van stops at every sixth block and a school bus stops at every tenth block.
We have to find the common stops at which they both stop if they start from a same entrance.
∴ We need to find the LCM of 6 and 10
The LCM of 6 and 10 is 2 × 3 × 5 = 30. Firstly both will stop at 30th block, then 60th block and lastly at 90th block.