Mathematics
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OpenStudy (anonymous):
What is the volume of the prism?
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OpenStudy (anonymous):
ganeshie8 (ganeshie8):
Volume of prism = (base area)*(height)
ganeshie8 (ganeshie8):
start by figuring out what could be the `base` and `height `
OpenStudy (anonymous):
Is it 1200?
ganeshie8 (ganeshie8):
nope, you need to count area of one base face only... not both the faces
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OpenStudy (anonymous):
but I got 150 for the base area then multiplied it by 8.
ganeshie8 (ganeshie8):
whats your base shape ?
triangle or rectangle ?
OpenStudy (anonymous):
15x10=150?
OpenStudy (anonymous):
Rectangle.
ganeshie8 (ganeshie8):
thats a mistake, not everything lying on bottom is a base
here, the base is a triangle
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OpenStudy (anonymous):
How do you know what's a base and what's not?
ganeshie8 (ganeshie8):
remember this :
for a prism, the opposite faces look identical for a base
ganeshie8 (ganeshie8):
the prism is just sleeping... so its base falls on sides
ganeshie8 (ganeshie8):
base = triangle
height = 10
work it now
OpenStudy (anonymous):
OH!
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OpenStudy (anonymous):
So 8*15/2?
ganeshie8 (ganeshie8):
yes thats the base area
OpenStudy (anonymous):
Okay.
ganeshie8 (ganeshie8):
multiply it by the height for the volume
OpenStudy (anonymous):
What's the height?
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ganeshie8 (ganeshie8):
if the triangle is base,
what will be the height ?
OpenStudy (anonymous):
Would it be 15?
ganeshie8 (ganeshie8):
think of rotating the prism by 90 degrees towards you
ganeshie8 (ganeshie8):
so that the triangular base stays on bottom
ganeshie8 (ganeshie8):
then height will be 10 right ?
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ganeshie8 (ganeshie8):
height is the distance between two base faces
ganeshie8 (ganeshie8):
here,
height = distance between two triangular bases
= ?
OpenStudy (anonymous):
Oh so the height is 10.
OpenStudy (anonymous):
So 60x10=600
ganeshie8 (ganeshie8):
Yes !
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ganeshie8 (ganeshie8):
nope
OpenStudy (anonymous):
Thank you so much. These prisms are so confusing.
ganeshie8 (ganeshie8):
whats the area of one base ?
OpenStudy (anonymous):
No?
ganeshie8 (ganeshie8):
Area of base = 8*15/2
= ?
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OpenStudy (anonymous):
120 time 10?
OpenStudy (anonymous):
The base area is 60
ganeshie8 (ganeshie8):
Yes ! base area = 60
OpenStudy (anonymous):
So multiply 60(BA) by 10(H)?
ganeshie8 (ganeshie8):
Oh! my bad !! you're right !!! i got confused earlier >.<
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OpenStudy (anonymous):
Haha it's fine.
ganeshie8 (ganeshie8):
600 is correct! good job :)
OpenStudy (anonymous):
THANK YOU.
OpenStudy (anonymous):
You deserve 10 metals!
OpenStudy (anonymous):
:D
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ganeshie8 (ganeshie8):
no, you deserve them :)