Discussion in 'Community Discussion' started by gregdrummeraz, Jun 16, 2008.

1. gregdrummeraz macrumors 6502

Joined:
Jun 7, 2007
Location:
Glendale, az
#1
The St. Louis River tank is a trapezoidal prism. The height of the trapezoidal base is 24 ft, and the two bases are 3 ft and 7 ft. If the height of the tank is 3 ft 6 in., what is the volume of the tank?

I'm Stumped... again.

2. dukebound85 macrumors P6

Joined:
Jul 17, 2005
Location:
5045 feet above sea level
#2
height times average of bases is the area

then times it by the depth to get volume

3. siurpeeman macrumors 603

Joined:
Dec 2, 2006
Location:
the OC
#3
more generally, the volume of a prism can be found by multiplying the base area and the height of the prism. and as the above poster mentioned, the area of the trapezoid is the average of the bases times the height.

4. gregdrummeraz thread starter macrumors 6502

Joined:
Jun 7, 2007
Location:
Glendale, az
#4
Here were my choices.

420ft^3
400ft^3
380ft^3
375ft^3

5. dukebound85 macrumors P6

Joined:
Jul 17, 2005
Location:
5045 feet above sea level
#5
Edit: just use the above equations to get answer

it is one of the choices lol

6. TuffLuffJimmy macrumors G3

Joined:
Apr 6, 2007
Location:
Portland, OR
#6
Four twenty!

maybe you should have listened to what the other posters said and tried to learn something for yourself.

7. gregdrummeraz thread starter macrumors 6502

Joined:
Jun 7, 2007
Location:
Glendale, az
#7
And I think it is either 380 or 420..

idk.. I really suck at this kind of math.

8. dukebound85 macrumors P6

Joined:
Jul 17, 2005
Location:
5045 feet above sea level
#8

A=3.5 *(7+3)/2
A=17.5ft^2

V= 24 *A=24*17.5
V=420ft^3

I hope you get the hang of following equations as if you go into any scientific major in college and cant do this, you are well in trouble lol

Joined:
Apr 6, 2007
Location:
Portland, OR
#9