Question

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Answer 1

so you are trying to find the least common multiple of 9 and 21?

Answer 2

Yes

Answer 3

factorize 9 and 21
what do you get?

Answer 4

3

Answer 5

9 = 3 x 3 21 = 7 x 3

Answer 6

yes. what factor do you see in both of them?

Answer 7

3

Answer 8

you can take one of the 3s out, then multiply the rest of the factors together.
Just this time, divide by 9 and 21 just to prove you can.

Answer 9

So how am i going to get the time it will ring simultaneously again? hehe

Answer 10

the next time the bell will ring is the LCM number of minutes after 12:00

Answer 11

definition of LCM: the smallest number that is divisible by both the numbers

Answer 12

I just explained all this to you so you could figure out the answer
so the answer is? :)

Answer 13

1:03???