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# C4 HELP

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1. Can someone help me with q2b

https://a086a5a2f39bda93734c56a63fab...%20Edexcel.pdf

basically, i dont understand why they cubed the 4.

ms:
https://a086a5a2f39bda93734c56a63fab...%20Edexcel.pdf

thanks
2. Because there is a volume scale factor. The original to the object has a scale factor of 4 and so areas would go up by 16 and volumes by 64
3. (Original post by nerak99)
Because there is a volume scale factor. The original to the object has a scale factor of 4 and so areas would go up by 16 and volumes by 64
how comes it goes to 64? is there a rule or something
4. If you scale a thing by a ration a:b then areas go up by a scale of a^2:b^2 and volumes by a^3:b^3

So, for example if I scale a 1,1,1 cube by a ration 1:3. The side length goes from 1,1,1 to 3,3,3. Each face area from 1x1=1 to 3x3=9 (i.e 3^2) so 6 faces go from 6x1 to 6x9=54 which is still a area ratio of 1:9 and the volume from 1x1x1=1 to 3x3x3=27 (i.e 3^3).

Is that clearer?
5. (Original post by Lilly1234567890)
how comes it goes to 64? is there a rule or something
you square the length scale factor to get the area scale factor

you cube the length scale factor to get the volume scale factor
6. (Original post by the bear)
you square the length scale factor to get the area scale factor

you cube the length scale factor to get the volume scale factor
(Original post by the bear)
you square the length scale factor to get the area scale factor

you cube the length scale factor to get the volume scale factor
(Original post by nerak99)
If you scale a thing by a ration a:b then areas go up by a scale of a^2:b^2 and volumes by a^3:b^3

So, for example if I scale a 1,1,1 cube by a ration 1:3. The side length goes from 1,1,1 to 3,3,3. Each face area from 1x1=1 to 3x3=9 (i.e 3^2) so 6 faces go from 6x1 to 6x9=54 which is still a area ratio of 1:9 and the volume from 1x1x1=1 to 3x3x3=27 (i.e 3^3).

Is that clearer?
thanks !
7. (Original post by Lilly1234567890)
thanks !
no worries... don't be afraid to ask us stuff

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