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Help me with my maths homework please!!!!!

I have this maths homework and it's due tomorrow. I need immediate help.

The question is:
The HCF of two numbers is 18. Their LCM is 630. What are the two numbers?

Reply 1

Muttley79

Original post by Gefforyson

You probably have this explained on the exercise given but I will give a recap...

First, factor out the numbers:
18 = 2*9 = 2*3*3
630 = 63*10 = 7*9*2*5 = 2*3*3*5*7

I've not checked what you wrote but PLEASE edit as full solutions are not allowed on the Maths forum. The bit I've quoted is enough of a hint ...

Reply 2

Gefforyson

Original post by Muttley79

I've not checked what you wrote but PLEASE edit as full solutions are not allowed on the Maths forum. The bit I've quoted is enough of a hint ...

Sorry, yes my bad I am quite new to this game and am trying to be helpful to the forum. I can see that what I wrote was probably less of a help but rather an encouragement to just copy the answer...

Reply 3

Notnek

Original post by Muttley79

I've not checked what you wrote but PLEASE edit as full solutions are not allowed on the Maths forum. The bit I've quoted is enough of a hint ...

It's been removed. Please edit your post to remove the full solution from the quote, thanks :smile:

Reply 4

Muttley79

Original post by Notnek

It's been removed. Please edit your post to remove the full solution from the quote, thanks :smile:

I did not quote the full solution ...

Reply 5

Notnek

@Muttley79 sorry just realised that you only quoted part of the solution.

Reply 6

Muttley79

Original post by Notnek

@Muttley79 sorry just realised that you only quoted part of the solution.

I usually edit so the person can see what might have been OK as a hint ... no worries :smile:

Reply 7

Gefforyson

Original post by Notnek

It's been removed. Please edit your post to remove the full solution from the quote, thanks :smile:

I had...

I will give you a starting block to approach this question, think about factorising the HCF and LCM to get:

18 = 2*9 = 2*3*3
630 = 63*10 = 7*9*2*5 = 2*3*3*5*7

Now think what these two prime factorisations can tell you about the two numbers the you want. Hope this is of help.

Reply 8

Muttley79

Original post by Gefforyson

Sorry, yes my bad I am quite new to this game and am trying to be helpful to the forum. I can see that what I wrote was probably less of a help but rather an encouragement to just copy the answer...