Question 225037
The width of a rectangle is one third of the length.  If the perimeter is 20 cm,find the width.


Step 1.  The perimeter P means adding up all four sides of a rectangle.


Step 2.  Let w be the width


Step 3.  Let 3w be the length since the width is one-third the length


Step 4.  Then P=w+w+3w+3w=8w=20 since the perimeter P is 20 cm.


Step 5.  Solving the equation in Step 4 leads to the following steps


Divide by 8 to both sides of the equation


{{{8w/8=20/8}}}


{{{w=5/2}}} and 3w=15/2 and P=2(5/2+15/2)=20 which is a true statement.


Step 6.  ANSWER:  The width is 5/2 cm.


I hope the above steps and explanation were helpful. 


For Step-By-Step videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry please visit http://www.FreedomUniversity.TV/courses/Trigonometry. 


Also, good luck in your studies and contact me at john@e-liteworks.com for your future math needs.


Respectfully, 
Dr J