Finding the Volume of Prisms

Today we started off in math class with correcting 7.1 numbers 3, 4, 5, 7, 9, 11, 13.
We then started on working on 7.2 and that is what I am going to show you what to do.

Find the Volume of a Triangular Prism

First you find the area of the triangle. Remember the formula, if you don't it is:
A=(b x h)/2
A=(13 x 8)/2
A=104/2
A=52cm2

Once you have figured that out you take the answer you got and multiply it by the height so like this:
V=A x H
V=52 x 12
V=624cm3

Remember that behind the final answer the units must be cm3, mm3, or m3. Not cm2, mm2, or m2 because that is what you use for area.

Finding the Volume of a Rectangular Prism

First off you must find the area of the base which the formula to find that out is:

A= l x w
A= 3 x 4
A= 12cm2

You take what you have there and multiply it by the height:

V= 12 x 12
V= 144cm3

Remember as well as the rectangular prism you must have the right units (cm2, mm2, or m2).

Finding Only the Certain Amount of Volume



First find the area of the triangle (A= (b x h)/2)
Second take the Area multiplied by the height of the prism
Thirdly the part we haven't covered in this post is take the volume multiplied by how full it is:

V= 642/1 x 1/3
V=642/3= 214cm3

The same goes for a rectangular prism.

ELA

In Ela today we typed out our Dear Abby letters for our newspaper. Right after that we got a different Dear Abby. You were suppose to read it and then give it a reply.
We also started writing out our seven articles for the newspaper.
Lastly we silent read for 10 minutes.

Correcting and Newspapers

Math- In Math today we did some correcting and some helping. We corrected chapter 7: Volume; Get Ready.
Right prisms and right cylinders have lateral faces that meet the base at 90%

Right Cylinder~-~-~-~-~--~-~Not A Right Cylinder
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Using mental math includes estimating. 3 ways to estimate are: round both down (4.5+67= 4+60), round both up (4.5+67= 5+70) or round one up and one down (4.5+67= 5+60).

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A question lots of people had trouble with was 3. b) and c).

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3. Calculate the area of each shaded region. Round your answers to the nearest tenth.

B)

First you have to find the area of the square. Then the area of 1 circle then times it by 4.

Since 6cm is the radius of 1 circle and 2 circles are side by side you times the radius by 4

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6x4=24cm

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a=l x w

a=24x24

a=576
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c=x

c=x3.14

c=36x3.14

c=452.16

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576-452.16= 123.8
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C)

a= (bxh)2

a= (45x19)2

a=8552

a=427.5

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c= x

c= x 3.14

c= 64x 3.14

c=200.96

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427.5-200.96= 226.5

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E.L.A.- Today in E.L.A. we read our articles we made yesterday. (article #3, Headline only). After that Mr. O read the actual article. Then we talked about a column named Dear Abby, then Dear Annie. We discussed those for a bit and then wrote our own (without our name). Mr. O will then hand them out sometime to random people and they will answer them. Once we were done we had free time.

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HOMEWORK:

Left side of 7.1 Understanding Volume
Dear Abby or Annie; scenario and question.