## Tuesday, February 15, 2011

### Christian's HWB Post

Pages: 78-79

Questions: 5, 8 and 9

5. What is the volume of a right prism that has a base with an area of 15cm2 and a height of 7cm?

V = 15cm2 x 7cm

V = 105cm3

7. Calculate the height of each rectangluar prism.

a) 63cm3 ÷ 9cm2 = 7cm

b) 26m3 ÷ 4m2 = 6.5m

9. Chad wants to cut back on the amount of treats he is eating. He has two chocolate bars to choose from. Which one has less chocolate? Show your thinking.

The first bar was:
V = 26cm2 x 2cm
V = 52cm3

The second bar was:
V = 5.25cm2 x 14.5cm
V = 76.125cm3

The first chocolate bar has less chocolate.

Cylinder Volume and Volume Problems

7.3

a) V = pi.r.r.h
V = 3x2x2x10
V = 120m^3

b) V = pi.r.r.h
V= (3.14x2 x2) x 10.5
V = 131.88m^3

7.4

d/2 = r
8 / 2 = r
4cm = r

V = pi.r.r.h
V = (3.14x4x4)x40
V= 2009.6cm^3

The capacity of the pipe is 2009.6cm^3

#### 1 comment:

1. Good job Christian! I like how you were is nice and organized. Next time you should add some color to your post to make it more interesting!