Grade 7 | Unit 2 | Lesson 7: Comparing Relationships with Tables | Practice Problems

Decide whether the table represents a proportional relationship and find the constant of proportionality. How loud a sound is depending on how far away you are.

• Distance to listener (ft)	Sound level (dB)
  5	85
  10	79
  20	73
  40	67

• Not proportional since the ratio of distance to listener to sound level is not always the same.

Decide whether the table represents a proportional relationship and find the constant of proportionality. The cost of fountain drinks at Hot Dog Hut.

• Volume (fluid ounces)	Cost ($)
  16	$1.49
  20	$1.59
  30	$1.89

• Not proportional since the ratio of volume to cost is not always the same.

• This is not a proportional relationship since the ratio of price to distance traveled is not always the same.

A rabbit and turtle are in a race. Is the relationship between distance traveled and time proportional for either? If so, write an equation representing the relationship. Turtle’s run.

• Distance (meters)	Time (minutes)
  108	2
  405	7.5
  540	10
  1,768.5	32.75

• Proportional

• Not Proportional

For each table, answer: What is the constant of proportionality? 1st Table.

• 7

For each table, answer: What is the constant of proportionality? 2nd Table.

• a	b
  3	360
  5	600
  8	960
  12	1440

• 120

For each table, answer: What is the constant of proportionality? 3rd Table.

• a	b
  75	3
  200	8
  1525	61
  10	0.4

For each table, answer: What is the constant of proportionality? 4th Table.

Kiran and Mai discuss whether doubling the dimensions of a rectangular field also doubles the distance to its diagonal opposite corner. Do you agree with either of them?

• The diagonal will scale by a factor of 2.

• The diagonal will be more than twice as far.

• Kiran is correct.