Direct, Inverse, Combined, Joint Variation

The distance it takes to stop a car varies directly as the square of the speed of the car. If it takes 112 feet for a car traveling at 40 miles per hour to stop, what distance is required for a speed of 65 miles per hour?

• 308.05 ft

• 295.75 ft

• 296.09 ft

• 253.5 ft

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

Determine the type of variation.

• Direct

• Inverse

• None

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

The frequency of a vibrating string varies inversely as its length. A string 3 feet long vibrates 175 cycles per

second. Find the frequency of a 5 foot string.

• 105 cycles

• 291.7 cycles

• 2625 cycles

• 332 cycles

Determine the type of variation.

• Direct

• Inverse

• None

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

Question: What is the relationship between two variables in direct variation?

• A) direct variation

• B) inverse variation

• C) neither direct nor inverse variation

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

The equation    
w = 10chs  represents:

• direct variation

• inverse variation

• joint variation

• none of these