Ok...Please help with my maths question!!

[KoreaJjang]

I'm suk at maths so I need ur help please!!
I stole one of the test paper we are going to do next week...and I'm trying to study it..but can't seem to find this question out..
I'm year 10 and this may be easy question for u guys...anyway PLEASE help!!! PLEASE~I asked my friend and they don't know so ur my only hope!!

Question
1. A right prism has a volume of 1449m3(cubic). Find the cross-sectional area if the prism as a height of 8.4 m

2. A cube has a surface area of 1350cm2(squared). Find its volume.

3. Find the radious of a cone which hold 115.5cm3(Cubic) if ice cream if the ice cream is smoothed off at the top and if the cone had a vertical height of 9 cm (Let pi=22/7)

PLEASE help me...Its hard for me so....Please~~

 

[PhiLLer]

e=mc2
Simple really.

 

[Crazy Rangas]

lol u stole the test, srry carnt help only in grade 10 : (

 

[KoreaJjang]

ummm...sorry but I'm really bad at maths...wats that again??

 

[Haukur Gudnason]

Could've used the time spent online to at least keep up with your syllabus.

But I do feel your pain.

The answer is always: x or y

 

[Crazy Rangas]

lol i odnt understand anything u _____________ said

 

[leungtl]

Download F2K for your Graphics Calculator (If you're using TI-83).

Solves all your problems

 

[KoreaJjang]

Thanks for ur help guys...My figured it out!! thx BYE~~

 

[Parra Power]

Re: Ok...Please help with my maths question!!

Originally posted by KoreaJjang
1. A right prism has a volume of 1449m3(cubic). Find the cross-sectional area if the prism as a height of 8.4 m

the crossection area will be equal with the cross section area in a prism.

as the formula for the a prism is base x height, you can say crossection area = 1449/8.4

so the crossection area is 172.5

Originally posted by KoreaJjang
2. A cube has a surface area of 1350cm2(squared). Find its volume.

a cube has six faces. so 1350 is 6x the size of one face. therefore the area of face is 225cm squared. the face of a cube is a square, and the area of a square is found by A^2 (length of a side squared)

so A^2 = 225
so A = 15

the volume of a cube is A^3. and 15^3 = 3375

Originally posted by KoreaJjang
3. Find the radious of a cone which hold 115.5cm3(Cubic) if ice cream if the ice cream is smoothed off at the top and if the cone had a vertical height of 9 cm (Let pi=22/7)

the volume of a cone is 1/3 x pi x height x r^2.

115.5 = 1/3 x 22/7 x 9 x radius^2
115.5 = 198/21 x r^2
r^2 = 12 1/4


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probably got some wrong, but im bored and that burnt a few minutes

 

[Parra Power]

Originally posted by Crazy Rangas
lol u stole the test, srry carnt help only in grade 10 : (

bah........................ im in yr10 too

 

[KoreaJjang]

UR A MATHS GENIOUS!! PARRA!! THANKS ALOT THOUGH I FINISHED

 

[Mutt]

god help you on the english tests.

 

[gagiz]

LMFAO!!!!!!!!!!!!!!!!!!!!!!!!!!!Nice one Mutt

 

[Tom]

Re: Re: Ok...Please help with my maths question!!

Originally posted by Parra Power
the crossection area will be equal with the cross section area in a prism.

as the formula for the a prism is base x height, you can say crossection area = 1449/8.4

so the crossection area is 172.5



a cube has six faces. so 1350 is 6x the size of one face. therefore the area of face is 225cm squared. the face of a cube is a square, and the area of a square is found by A^2 (length of a side squared)

so A^2 = 225
so A = 15

the volume of a cube is A^3. and 15^3 = 3375



the volume of a cone is 1/3 x pi x height x r^2.

115.5 = 1/3 x 22/7 x 9 x radius^2
115.5 = 198/21 x r^2
r^2 = 12 1/4


____________________________________________________

thats what i got

TROD.

 

[hunttherock]

Bah, All this is so easy compared to the crappy maths I've to do.

Laplace Transforms
Bessel functions
Differential Equations.......