Thursday, February 17, 2011

John Chua's textbook work : volume pages 259-260 #7,12,14


Formula used:
Area of the base x height
b x h1 x h2= volume

A)
7 x 7 / 2 = 24.5cm squared
24.5cm squared x 12 = 294cm cubed

B)
8.1 x 2.2 / 2 = 8.91m squared
8.91 x 15 = 133.65m cubed

C)
320 x 210 = 33,600mm squared
33,600 x 400 = 13 440 000mm cubed





A) height of prism (cm) = 10
how?
7 x 2 / 2= 7cm squared
70 / 7 = 10cm

B) height of triangle (cm) = 12
how?
1080 / 10= 180cm
180 x 2 = 216cm
216 /18 = 12cm

C)base(cm)=20
700 / 5 =140
140 x 2 =280
280 / 14 = 20





volume= 4800cm cubed]
how?
b x h1 x h2= volume
8x 15 / 2= 60cm squared
60cm squared x 80 = 4800cm cubed

Cylinder and Volume Problems



A)3x4x4=48cm^2
48cm^2 x 10cm= 480cm^3

b)3.14 x 4.1 x 4.1=53cm^2
53cm^2 x 11 = 583cm^3



R=d/2
R=10/2
R=5
R=8/2
R=4

outside radius 5cm
inside radius 4cm
height 40cm

pi x r x r = area of base

3.14 x 5 x 5 = 78.5cm^2
78.5cm^2 x 40 cm=3,140 <---- Outside Volume 3.14 x 4 x 4 = 50.24^2 50.24cm^2 x 40cm = 2009.6cm^3 <-------- Inside Volume 3140cm^3-2009.6cm^3= 1,130.4cm^3

2 comments:

  1. Good job John. Your post was very organized and you showed your work nicely. Next time try adding a video and/or link.

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  2. Good Job John. I like your post it is really organized and easy to understand. I agree with emily, next time your should add a video and a link.

    ReplyDelete