7.1 Inverse Variation

Which of the following is a direct variation?

• y=x+3
• yx=k
• 2xy=4
• 6x=y

What type of variation does this table represent?

• Direct
• Inverse
• Neither

Which equation shows an inverse variation?

• kx=y
• y3=x
• 6=yx
• y=k

What type of variation does this table show?

• Inverse
• Direct
• Both
• Neither

What type of variation is represented by this table?

• Direct
• Inverse
• Both 
• Neither

Given that y varies inversely with x, if x =7 and y = 4, what is y when x = 2?

• 14
• 10
• 2
• -14

Tags

CCSS.7.EE.B.3

CCSS.7.EE.B.4

Does the equation show an inverse variation? 
y=10/x

• yes
• no

Tags

CCSS.HSF.BF.A.1

CCSS.HSF.BF.B.4

CCSS.HSF.IF.A.1

Given the following equation, identify the constant k.
y = 54/x

• There is one.
• k = x
• 54
• y = k

Tags

CCSS.7.EE.A.2

CCSS.7.EE.B.4

CCSS.7.RP.A.2

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

Tags

CCSS.HSA.CED.A.1

CCSS.HSA.CED.A.2

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 

Tags

CCSS.HSA.CED.A.1

CCSS.HSA.CED.A.4

CCSS.HSA.SSE.A.1