Direct or Inverse Proportionality

The amount of money earned on a job is directly proportional to the number of hours worked.  If $70.00 is earned in 5 hours, how much money is earned in 22 hours of work?

• $2

• $308

• $1.57

• $265

Is the given table a direct variation? If so, what is the constant of proportionality?

• Yes; 1/4

• Yes; 4

• Yes; 1/2

• No

Does the relationship represent direct variation?

• Yes

• No

Trina's paycheck earnings varies directly as the number of hours she works. If she works 19 hours and earns $187.15, what should she earn if she worked 40 hours?

• $394

• $440

• $472.80

• $512.20

y varies directly with x, and y is 16 when x is 32. Which equation represents this situation?

• y=32x

• y=16x

• y=2x

• y=(1/2)x

The interest received on a savings account varies directly with the amount deposited. Daniel received $55.35 in interest on $1230 he deposited. How much interest would Daniel have received if he had deposited $2000 into his account?

• 34.04

• 90.00

• 1,285.35

• 44,444.44

Which of the following represents indirect variation?

• y = kx

• y = k/x

• y = x/k

• y = mx + b

Which of the following represents direct variation?

• y = kx

• y = k/x

• y = x/k

• y = mx + b

What is the constant (k) in this inverse variation?
y = 400/x

• x

• y

• 400

• Not enough information given

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

• 300

• 75

• 1,875

• 12