Question 1155367
2 ferries sail from port A to port B. The first ferry departs again from port A after 4 days, while the second ferry departs after 7 days. On March 1, both ferries depart simultaneously from port A. On which date Will the ferries leave port A again at the same time in March?
solution 
Repetition Of A 4 days 
Repetition  of B is 7 days  
Lcm of 4 and 7 =28 
both started  at  March 01  they will again start together  0n 28 march  after 28 days