David was trying to sleep one night but there was too much noise around him? his clock ticked every 5 seconds , a tap was dripping every 7 seconds and his pet dog snored every 12 seconds he noticed n his clock that all three things happened together on the stroke of midnight (a) after how many second would all three things happen together again. (b) how many times would all three things happen together again between midnight and one o'clock

A) 420 seconds = 7 minutes

B) 8 times

Step-by-step explanation:

A) After how many second would all three things happen together again?

Solution:

His clock ticked every 5 seconds , a tap was dripping every 7 seconds and     his pet dog snored every 12 seconds. It all happens simultaneously = 5*7*12=420 seconds

B) How many times would all three things happen together again between    midnight and one o'clock

Since all these events happen together after every 420 sec = 7 mins and there are 60 mins between midnight and 1 o'çlock , thus 60/7 = 8 times