Inverse Proportion

y is inversely proportional to x, and y = 2 when x = 5. Write an inverse equation relating x to y.

Mathematical Equivalence

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The number of hours to paint a house varies inversely with the number of painters working. A 2400-square foot house can be painted in 27 hours by 6 painters. How many painters would need to work in order to paint the house in 18 hours?

• 8 painters

• 10 painters

• 9 painters

• 11 painters

The width of a rectangle varies inversely with its length. if the width is 4 when the length is 18, find the width when the length is 8.

• 9

• 72

• 36

• 2

6.The time it takes to travel a fixed distance varies inversely with the speed traveled. If it takes Pancho 52 minutes to bike to his fishing spot at 9.5 miles per hour, how long will it take him if he rides at 11 miles per hour?

• Direct Variation

• Inverse Variation

If y is inversely proportional to x and y=2 when x=6, find y when x=15.

• 0.8

• 1.5

• 3

• 5

If x is inversely proportional to y and x=10 when y=4, find the value of x when y=0.4.

• 100

• 75

• 50

• 25

If z is inversely proportional to ∛w and z=5 when w=8,

find the value of w when z=100.

• 1

• 0.1

• 0.01

• 0.001

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

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 

t is inversely proportional to v t=2 when v=6 Find the equation for t and v

• t = ¹²/_v

• t = ¹/₃ v

• t = ³/_v

• t = 12v