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Practice

7.1.5 Practice

7.1.5 • Practice

Complete the following questions to practice the skills you have learned in this lesson.

  1. Here are a few pairs of positive numbers whose sum is 50.
Row First number Second number Product
a 1 49  
b 2 48  
c 10 40  
    1. Find the product in Row a.
    1. Find the product in Row b.
    1. Find the product in Row c.

Use the following table to answer questions 2 – 5.

Here are some lengths and widths of a rectangle whose perimeter is 20 meters.

Row Length (meters) Width (meters) Area (square meters)
a 1 9  
b 3 7  
c 5    
d 7    
e 9    
  1. Complete the Width column of the table.
  1. Width in Row c
    1. Width in Row d
    1. Width in Row e
  1. Complete the Area column of the table. What do you notice about the areas?
    1. Area in Row a
    1. Area in Row b
    1. Area in Row c
    1. Area in Row d
    1. Area in Row e
  1. Without calculating, predict whether the area of the rectangle will be greater than or less than 25 square meters if the length is 5.25 meters.
  1. greater than
  2. less than
  1. Plot the points for length and area from your table. Do the values change in a linear way? Do they change in an exponential way?
  1. linear
  2. exponential
  3. linear and exponential
  4. not linear and not exponential

Use the following to answer questions 6 – 8.

Copies of a book are arranged in a stack. Each copy of a book is 2.1 cm thick.

Row Copies of book Stack height in cm
a 0  
b 1  
c 2  
d 3  
e 4  
  1. Complete the table.
    1. Stack height in Row a
    1. Stack height in Row b
    1. Stack height in Row c
    1. Stack height in Row d
    1. Stack height in Row e
  1. What is the difference in the height of the stack of books when a new copy of the book is added?
  1. How high is a stack of b books, in centimeters?
  1. 2.1 b
  2. 2.1 ( b − 1 )
  3. 2.1 + b
  4. ( 2.1 ) b