Direct Joint Combined Variation

The volume of wood in a tree varies jointly as the height of the tree and the square of the distance around the tree trunk. If the volume of wood is 15.84 cubic feet when the height is 22 feet and the distance around the trunk is 3 feet, what is the volume of wood obtained from a tree that is 32 feet tall having a measurement of 4 feet around the trunk?

• 44.96 ft³

• 49.96 ft³

• 40.96 ft³

• 32.96 ft³

If f varies jointly as q² and h, and f = 96 when q = 4 and h = 3, find q when f = 48 and h = 6.

• 4

• 2

• 6

• 3

Determine the type of variation.

• Direct

• Inverse

• None

• direct variation
• inverse variation
• neither direct nor inverse variation

• direct variation
• inverse variation
• neither direct nor inverse variation

• direct variation
• inverse variation
• joint variation
• none of these

What type of variation does this scenario represent?
The length of time you charge your cell phone
and the battery power 

• direct variation

• inverse variation

• joint variation

• none of these

• direct variation
• inverse variation
• joint variation
• none of these

State what type of variation the equation represents.

• Direct

• Inverse

• Joint

• None

A is in joint variation with B and square of C. When A = 144, B = 4 and C = 3. Then what is the value of A when B = 6 and C = 4?

• 12

• 36

• 384

• 96