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2. ok - let's call the lenght of one edge of a cube, or side of a square, 'x'. The area of a square (one face of a cube) is equal to x squared - so take the square root of the area to find x. Then the volume of a cube is x cubed. Does that help?
3. (Original post by cheshiremum)
ok - let's call the lenght of one edge of a cube, or side of a square, 'x'. The area of a square (one face of a cube) is equal to x squared - so take the square root of the area to find x. Then the volume of a cube is x cubed. Does that help?
id have defo failed this question then!
im uber bad at maths and my approach would have been to times 20 by all the sides of the cube and then times the total by 2 :/
4. (Original post by cheshiremum)
ok - let's call the lenght of one edge of a cube, or side of a square, 'x'. The area of a square (one face of a cube) is equal to x squared - so take the square root of the area to find x. Then the volume of a cube is x cubed. Does that help?
Square root of 20 would be 4.47 what would I do after this?
5. 4.47 cubed = 4.47 x 4.47 x 4.47 unless you're allowed to use a calculator then do 20^(3/2)....= 89.44 and remmeber to put the units in..cm3 (that should be a superscript 3) - you lose marks for forgetting the units.
6. (Original post by zXcodeXz)
Square root of 20 would be 4.47 what would I do after this?
So you've got the length of each side cube, with which you should be able to find the volume...
Spoiler:
Show
Volume is length x width x height
7. (Original post by cheshiremum)
4.47 cubed = 4.47 x 4.47 x 4.47 unless you're allowed to use a calculator then do 20^(3/2)....= 89.44 and remmeber to put the units in..cm3 (that should be a superscript 3) - you lose marks for forgetting the units.
Oh ok thanks for your help!
8. (Original post by TheOtherSide.)
So you've got the length of each side cube, with which you should be able to find the volume...
Spoiler:
Show
Volume is length x width x height
Thank you
9. (Original post by zXcodeXz)
Sorry for the late reply, but as above, the area of one side of a cube is where is the side length and you want to find , which the volume.
10. (Original post by shawtyb)
id have defo failed this question then!
im uber bad at maths and my approach would have been to times 20 by all the sides of the cube and then times the total by 2 :/
I'm going to say you are NOT uber bad at maths...either you weren't paying attention, or you've not been taught well, or you lack confidence! You can do this. Area of a square = x multiplied by x...volume of a cube = x multiplied by x multiplied by x. Believe in yourself, do a bit of practise, look up some papers with marking schemes and model answers - do the questions, then check the answers. You CAN do maths.
11. (Original post by Zacken)
Sorry for the late reply, but as above, the area of one side of a cube is where is the side length and you want to find , which the volume.
Thanks!
12. (Original post by cheshiremum)
I'm going to say you are NOT uber bad at maths...either you weren't paying attention, or you've not been taught well, or you lack confidence! You can do this. Area of a square = x multiplied by x...volume of a cube = x multiplied by x multiplied by x. Believe in yourself, do a bit of practise, look up some papers with marking schemes and model answers - do the questions, then check the answers. You CAN do maths.
no, trust me. i CANT do maths. i have problems with relaying information

i can barely times things by each other unless there easy.

volume of a cube for example 3x3x3. id think its 9 or 18. there the answers id have got
13. (Original post by zXcodeXz)
Thanks!
I'm moving this to the maths forum, try and post mathematical queries in there in the future. :-)
14. (Original post by Zacken)
I'm moving this to the maths forum, try and post mathematical queries in there in the future. :-)
Ok thanks and I will do
15. (Original post by zXcodeXz)
Ok thanks and I will do
No worries.
16. (Original post by shawtyb)
no, trust me. i CANT do maths. i have problems with relaying information

i can barely times things by each other unless there easy.

volume of a cube for example 3x3x3. id think its 9 or 18. there the answers id have got
Ah, I can see tha t might make things harder. YOu've got to break it down...3x3x3 = (3x3)x3 = (9)x3 = 27
Multiplication is adding things a series of times, so 3 x 2 is 3 lots of 2; 2+2+2 =6. 3x3 =3 lots of 3 = 3+3+3=9.
Do one multiplication first, then the next. Believing you can do it, or learn how to do it, is more than half the battle.
Or think about a practical example - instead of a cube of side 3, think of a box with 3 rows of 3 shirts, so 9 shirts in each box, then 3 boxes stacked on top of each other...so 3 boxes each with 9 shirts...so 27?
Good luck!
17. im usually ok if its really really simplified but after that day, il just have no idea
easy multiplication i can do but i cant even add things in my head, i can if its easy but beyond my idea of easy and il need to count on my hannds.
18. (Original post by zXcodeXz)
Square root of 20 would be 4.47 what would I do after this?
. that means that , meaning that is not irrational after all? I think I'm going to have to have a lie down.
19. (Original post by Ano123)
. that means that , meaning that is not irrational after all? I think I'm going to have to have a lie down.
No it's basically what same number times together to get 20
20. (Original post by zXcodeXz)
No it's basically what same number times together to get 20
Which is 4.47?

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