Direct and Inverse Practice

The number of shares varies directly with the amount of dividends received per year.  If Kim owns 5 shares of stock and received $24 per year, how many shares of stock will she need to receive $48? 

• y = 4.8x
• 2.5
• y = 4.8/x
• 10

Determine the type of variation:

_{(Hint: solve for y. Does the result look like one of our variation model equations?)}

x + 2y = 14

• Direct

• Inverse

• Neither

If m varies directly as p² and m = 20 when p = 2, what is the constant of proportionality?

• k=200
• k=1/5
• k=10
• k=5

Determine the type of variation: 

• Direct
• Inverse
• Neither

If z varies directly as t and inversely as the square of v, what is the equation model for this scenario?

• z=^kt/_v
• z = ^kt/_v²
• z=ktv²
• z=^k/_tv²

The sales at a baseball game vary directly with the number of people attending.  If the sales for a game are $12,000 when 800 people attend, write an equation that represents this.  

• y = 9600000k
• y = 15k
• y = 15/k
• y = 9600000/k

The width of a rectangle varies inversely with its length.  If the width is 6 when the length is 24, give an equation that shows the relationship. (Hint: find the k value)

• W = 4L
• W = 144L
• W = 4/L
• W = 144/L

The number of workers varies inversely with the time in days to complete a project.  4 workers can complete a certain project in 24 days.  How many workers are needed to do the job in 18 days? 

• y = 96/x
• 1728
• 5
• 6

Determine the type of variation:

• Direct
• Inverse
• Neither

The time it takes to bake a cake varies inversely with the oven temperature. If it takes 30 minutes to bake a cake at 300 degrees, how long will it take to bake a cake at 350 degrees? 

• y = 9000x
• 25.7 
• y = 90/x
• 26