GL pack 2 paper 6- Q 41-help!

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Roz12
Posts: 118
Joined: Wed Nov 02, 2011 10:45 pm

GL pack 2 paper 6- Q 41-help!

Post by Roz12 »

Hi all,

There are many volume Q's like these but can't seem to work them out?

What is the largest number of cubes of side 0.5cm that will fit into the cuboid above?


Cuboid is 3cm by 2cm by 1cm.


Thanks
mystery
Posts: 8927
Joined: Tue Jul 21, 2009 10:56 pm

Re: GL pack 2 paper 6- Q 41-help!

Post by mystery »

Volume of tiny cube is 0.125. Volume of cuboid is 6.

6 /0.125 = 48
Okanagan
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Joined: Mon Aug 22, 2011 9:20 pm
Location: Warwickshire

Re: GL pack 2 paper 6- Q 41-help!

Post by Okanagan »

Or a different way to get the same answer, which may be easier to visualise:

If the cuboid is 3cm by 2cm by 1cm how many of the 0.5 cm cubes would fit along each side?
6 x 4 x 2 = 48
Roz12
Posts: 118
Joined: Wed Nov 02, 2011 10:45 pm

Re: GL pack 2 paper 6- Q 41-help!

Post by Roz12 »

Thanks :)
Roz12
Posts: 118
Joined: Wed Nov 02, 2011 10:45 pm

Re: GL pack 2 paper 6- Q 41-help!

Post by Roz12 »

I don't think my daughter will be able to work out 6/0.125?
Okanagan
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Location: Warwickshire

Re: GL pack 2 paper 6- Q 41-help!

Post by Okanagan »

maybe worth working on some common fraction / decimal equivalents then:
0.5 = 1/2
0.25 = 1/4
0.125 = 1/8
etc

divide by 0.125 = divide by 1/8 = multiply by 8

But she'll probably find the visual method of how many could be lined up alongside the bigger object easier to comprehend.
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: GL pack 2 paper 6- Q 41-help!

Post by Guest55 »

Oknagan's method is best - just dividing volumes doesn't always work if a whole number of cubes don't fit along edges.

Mystery - your method is flawed and could cause errors.
mystery
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Joined: Tue Jul 21, 2009 10:56 pm

Re: GL pack 2 paper 6- Q 41-help!

Post by mystery »

Yes, it is. I should have added that it is ok to do it that way because you can see that a whole number of cubes will fit along each edge as 0.5 is a factor of all the given dimensions. Sorry about that. Same principle if it was a 2 dimensional question asking about whole numbers of tiles.
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