0 votes
670 views
in Mathematics Form 1 by

 Three bells ring at regular intervals of 9mins,15mins and 21mins.The bells ring at 5.45pm.

By 10.00am next day, how many times will they have rung together?

18 Answers

0 votes
by
5 times

0 votes
by
Lcm of 9,15,21
0 votes
by
LCM of 9,15,21.answer divide by 60

0 votes
by
LCM OF 9, 15 and 21 is 315
Change 315 to hours and it will be 5hrs 15 minutes 
This means that it will take 5hours 15 minutes intervals
Get the time difference between 10.00am and 5.45pm and it is 16 hours 15 minutes 
Then divide the difference with the time interval to get the number of times
And the answer is 3 times.
0 votes
by
1

0 votes
by
14 by

0 votes
by
5

0 votes
by
3 times
0 votes
by
3 times

0 votes
by
7:10pm
Welcome to EasyElimu Questions and Answers, where you can ask questions and receive answers from other members of the community.

6.4k questions

9.6k answers

6 comments

590 users

...