Maths Help Needed

[grasscarp]

I was trying to help a child with maths homework this evening but could not manage this one.
There are two numbers
If 3 is the highest common factor, and 45 is the lowest common denominator what are the two numbers?
any help much appreciated.

[ladyalex]

I cannot work that one out at all...though it is a long time since I was at school.....the factor/denominator are the wrong way round, are they ?

[grasscarp]

No, that is how they were in the question. I havent got the sheet in front of me, and will see they young lad again tomorrow. It has to be handed in next Friday!

[ladyalex]

Sorry, meant is it possible that 3 is the lowest common denominator and 45 is the highest common factor ?
If so, would the numbers be 45 and 135 ?

[Buenchico]

I hope that neither of you two were in my maths classes when I was teaching ;-)

9 & 15

Chris

[grasscarp]

Chris. you are a hero. I will pretend tomorrow that I worked it out!!!! Many thanks.

[ladyalex]

How do you work it out then , buenchico ?

[quinie]

Buenchico. I was just working it out-honest! It was taking me a while-60+ years since I did higher maths.

[grasscarp]

I hope for our sake that Buenchico will look back in here, since we were not lucky enough to be in his class. I dont think I was ever in his class - with a face like that I would have remembered.

[Buenchico]

45 factorises as (1 x) 3 x 3 x 5

Both of the numbers we seek must divide into it so the only possible numbers to be considered are 1, 3, 9 (=3 x 3), 15 (=3x5) and 45.

But 3 must divide into both of the numbers we're seeking, so we can immediately exclude 1 from the possible pairings. That doesn't leave a lot to try!

[ladyalex]

I'll stick to crosswords from now on......

(Thanks, Buenchico)

[grasscarp]

Many thanks teacher. (Buenchico)

[quinie]

Thanks for explanation, Buenchico

[Fibonacci]

There ia another answer the two numbers could be 45 & 3.

[grasscarp]

Thanks for your input Fibonacci. what were you doing getting up so early?