Inverse Variation- Word Problems

When building a house, the number of days required to build is inversely proportional to with the number of workers. One house was built in 85 days by 5 workers. How many days would it take to build a similar house with 25 workers?

• 17

• 20

• 30

• 425

When renting a limo for prom, the number of people varies inversely with the cost per person. Originally there were 6 people and the cost per person was $48. If the number of people changed to 12, what would be the new cost per person?

• $24

• $96

• $8

• $4

In kickboxing, it is found that the force, f, needed to break a board, varies inversely with the length, l, of the board. Write and solve an equation to answer the following question: If it takes 15 lbs of pressure for DJ to break a board 4 feet long, how many pounds of pressure will it take Emily to break a board that is 10 feet long?

• 6

• 3

• 60

• 12

The amount of time it takes for an ice cube to melt varies inversely to the air temperature, in degrees. At 55 degrees Fahrenheit, the ice will melt in 35 min. How long will it take the ice to melt if the temperature is 125 degrees?

• 15.4 minutes

• 17.5 minutes

• 22.6 minutes

• 79.5 minutes

When renting a limo for prom, the number of people varies inversely with the cost per person. Originally there were 6 people and the cost per person was $48. If the number of people changed to 12, what would be the new cost per person?

• $24

• $96

• $8

• $4

Boyle’s Law states that, for a fixed amount of gas, the volume of the gas at a constant   temperature is inversely proportional to the pressure. If a certain gas occupies 9.84 liters   at a pressure of 50 centimeters of mercury (cm Hg), what is the approximate pressure   when the volume is increased to 12 liters?

• 39.8 cm Hg
• 41.0 cm Hg 
• 43.2 cm Hg
• 45.1 cm Hg

The time it takes to fly from Los Angeles to New York varies inversely as the speed of the plane. If the trip takes 6 hours at 900 km/h, how long would it take at 800 km/h?

• 5.33 hours 
• 6.75 hours 
• 12 hours 
• 10 hours 

Which of the following represents indirect variation?

• y = kx

• y = k/x

• y = x/k

• y = mx+b

Tags

A.8

The cost per person to rent a mountain cabin is inversely proportional (varies inversely) to the number of people who share the rent. If the cost is $36 per person when 5 people share, what is the cost per person when 8 people share?

• $22.50
• $57.60
• $1.11
• $12.50

Tags

CCSS.HSA.CED.A.1

CCSS.HSA.REI.B.3

CCSS.HSA.SSE.A.1