inverse direct variation

y varies directly as x, if y=4 when x=3, find x when y=-12

• -16
• 16
• -9
• 9

The sales at a baseball game vary directly with the number of people attending.  If sales for a game are $12,000 when 800 people attend, determine attendance if sales are $30,000

• 1200 people
• 1500 people
• 2000 people
• 2400 people

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

The gallons of water used to take a shower varies directly with the number of minutes in the shower. If an 8 minute shower uses 48 gallons of water, find the constant of variation.

• 1/6
• 6
• 8
• 48

Is the following graph direct, inverse, or neither?

• Direct
• Inverse
• Neither

Is the following graph direct, inverse, or neither?

• Direct
• Inverse
• Neither

Suppose y varies inversely with x.
If y = 150 when x = 2, find y when x = 25.

• 300
• 75
• 1,875
• 12

The number of kilograms of water in a person’s body varies directly as the person’s mass.  A person with a mass of 90 kg contains 60 kg of water.  How many kilograms of water are in a person whose mass is 75 kg?

• 50 kg water
• 72 kg water
• 94 kg water
• 150 kg water

Is this a direct variation?

• yes
• no