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1. Hi!

Can anybody solve this similarity Problem. I have tried to use a scaling argument however it proved unsuccessful. For instance,

A statue weighs 840kg. A similar statue was made out of the same material but two fifths the height of the first one. What was the weight of the smaller statue?

So would you times the original weight of 340kg by 3/5 to get the weight of the smaller statue?

Help
2. 840 multiplied by 2/5
3. 840 X (2/5)^2 ???
4. 134kg.
5. 840x0.4x0.4x0.4
6. Thanks I did 840 x(2/5)^3

=53.8cm^3 which is correct

Thanks
7. If we use scaling, consider this:

Where is the mass of the first statue and is the mass of the second statue.

EDIT: Oops, you already did it
8. Advanced lol, you've seen nothing yet.
9. If the height of the second statue is 2/5 of the height of the first statue, and the statues are "similar", then the width and depth of the statue will also be 2/5 of the width and depth of the first statue. Therefore, the second statue is (2/5)^3, or 0.064 times the volume of the first statue. Given they are made from the same material, the mass will be directly proportional to the volume in this scenario, so the mass of the second statue will be 0.064*840 kg, or 53.76kg.

If this is indeed for "advanced calculus", I'm bound to have read the question wrong because this seems ridiculously easy...
10. sorry, i forgot that it would be cubed because the shape is 3D

what level of maths is this by the way? i dont mean to be rude but that is standard grade level in scotland so it has been a while since i did it
11. (Original post by Sophie Maywood)
Thanks I did 840 x(2/5)^3

=53.8cm^3 which is correct

Thanks

WTF, you asked for weight that is volume.

and is it 840 or 340
12. Is this really advance calculus?
As it seems pretty trivial to me.
13. (Original post by Simplicity)
As it seems pretty trivial to me.
It's not calculus.
14. Sorry it is around A* at GCSE ao it is pretty advanced for myself
15. 840*(2/5)^3.

Please do not lure people with 'advanced calculs' - do you even know what a derivative or integral is?

People like you bring this forum down. I hope you fail GCSE maths and in life.
16. Yes I actually do. A derivative starts at AS level mathematics and the concept of it is d/dy(x^n)=nx^n-1 where d is the derivative of the X^n in the brackets. Basically it menas the thing you have left whe you differentiate something.

Secondly, An intergral is ∫. You can get many forms of these, i.e a volume intergral, and area intergral (etc). When you inergrate something you're trying to find a fucntion that returns to what you started with when you differentiate something.

So, I may be weak at one aspect of mathematics, for instance similarity. Although I do read and research AS level maths in preperation for the course next year because I find maths interesting.

Oh, and thanks for the childish sarcastic comment, it sums you up. Get it "sums" you up!!!!
17. (Original post by Sophie Maywood)
Yes I actually do. A derivative starts at AS level mathematics and the concept of it is d/dy(x^n)=nx^n-1 where d is the derivative of the X^n in the brackets. Basically it menas the thing you have left whe you differentiate something.

Secondly, An intergral is ∫. You can get many forms of these, i.e a volume intergral, and area intergral (etc). When you inergrate something you're trying to find a fucntion that returns to what you started with when you differentiate something.

So, I may be weak at one aspect of mathematics, for instance similarity. Although I do read and research AS level maths in preperation for the course next year because I find maths interesting.

Oh, and thanks for the childish sarcastic comment, it sums you up. Get it "sums" you up!!!!
FAIL
18. Well you told him!
19. How childish are you DeanK2. She will probably be far better than you at your level when she reaches it (as will I)
20. (Original post by DeanK2)
Obviously wikkied with no understanding of anything at all. If you are so cough, 'well', cough, read up, why don't you tell me the integral of f(x) actually finds, given that f(x) = x^2?
For god sake, leave her alone

Yes she spelt the calculus wrong, used annoying exclamation marks and it isn't even calculus but there's no need to tell her to "fail in life" and challenge her to questions beyond the GCSE syllabus.

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