Math Is Fun Forum

Itsmeali

Member

Registered: 2016-07-23

Posts: 2

Area and Volume of Prisms and Pyramids.

Hello,
I am having a lot of difficulties finding out the formula and answer.
I posted the first question for now, and I'll post the rest after I get a hang on this one.

For 1 through 10, what is the area and volume of the given shape, if the length of one side of the base is 6, the height is 8, and the slant height is 10? (Not all shapes will require all three numbers.)

The shape is a right prism with:

1. an equilateral triangle as the base

ALateral area: 90; Volume: 288
BLateral area: 192; Volume: 64
CLateral area: 120; Volume: 240
DLateral area: 144; Volume: 72 √(3)
E Lateral area: 176; Volume: 18*√(15)
F Lateral area: 100; Volume: 288

Bob

Administrator

Registered: 2010-06-20

Posts: 10,640

Re: Area and Volume of Prisms and Pyramids.

hi Itsmeali

This looks like a CompuHigh question.  They like to pack a lot of questions in by giving the information once.  It doesn't quite work here because an equilateral end will have a base size and slant length that are the same.  Let's assume the triangles have a side length of 6 and the prism is  8 long.  (Hope that's what they intend)

The surface area consists of three identical rectangles and two triangular ends.  Lateral area should just mean the rectangles, so (6x8)x3 for that.

The volume is (area of an end) x the length so that would be (0.5 x 6 x 6(√ 3)/2) x 8.
I think this question may have been posted before so I'll have a search.

Bob

edit:  Yes, it was posted here http://www.mathisfunforum.com/viewtopic.php?id=22608  but Lisa didn't ask about Q1-5.  Some of the measurements on this sheet lead to impossible shapes, so we may have some fun here

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: Area and Volume of Prisms and Pyramids.

bob bundy,
You are making mountain out of a mole hill.
There are  multiple choices A... F for Q.1
The correct answer is D.

Last edited by thickhead (2016-08-08 20:11:56)

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{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

Bob

Administrator

Registered: 2010-06-20

Posts: 10,640

Re: Area and Volume of Prisms and Pyramids.

Thanks thickhead.  You may have missed my edit.  I agree D is the answer.  But what do they mean by the slant height is 10 ?

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: Area and Volume of Prisms and Pyramids.

(Not all shapes will require all three numbers.)

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

Itsmeali

Member

Registered: 2016-07-23

Posts: 2

Re: Area and Volume of Prisms and Pyramids.

Hi Bob,
Thanks for the help and sorry for the late response.
I have four formulas in which the lesson provided. I think that these formulas will help me find the answer to the questions.
Right Prism Area Theorem.
Lateral Area = Ph
Volume= Bh

Regular Pyramid Area Theorem
Lateral Area = 1/2(P)L
Volume= 1/3(Bh)