Education.com
Try
Brainzy
Try
Plus

Perimeter Word Problems Practice Questions

based on 1 rating
By
Updated on Oct 3, 2011

To review these concepts, go to Perimeter Word Problems Study Guide.

Perimeter Word Problems Practice Questions

Practice

Problems

  1. The measure of the base of an isosceles triangle is 10 units. If the legs each measure 2 units more than the base, what is the perimeter of the triangle?
  2. The sides of a scalene triangle are 12, 15, and 20 units, respectively. What is the perimeter of the triangle?
  3. A side of a square is represented by the expression 5x. If the perimeter is 40 units, what is the length of one side of the square?
  4. The length of a rectangle is three times its width. If the perimeter of the rectangle is 80 meters, what is the length of the rectangle?
  5. An area is enclosed with a fence in the shape of a regular pentagon. If each side of fencing is 35 meters long, what is the perimeter of the pentagon?
  6. A regular octagon has sides that each measure 20 cm. What is the perimeter of the octagon?

Solutions

  1. Read and understand the question. This question is looking for the perimeter of an isosceles triangle.
  2. Make a plan. The perimeter is the distance around the object. Add the lengths of the three sides of the triangle to find the perimeter. The length of the base is given.

    Carry out the plan. The lengths of the two legs of the triangle are two more than the length of the base side: 10 + 2 = 12. Add the three sides: 10 + 12 + 12 = 34 meters. The perimeter is 34 meters.

    Check your answer. To check this solution, start with the perimeter of 34 meters. If each side length is subtracted from this value, the result should be zero: 34 – 10 – 12 – 12 = 0, so this solution is checking.

  3. Read and understand the question. This question is looking for the perimeter of a scalene triangle.
  4. Make a plan. The perimeter is the distance around the object. Add the lengths of the three sides of the triangle to find the perimeter. All three side lengths are given.

    Carry out the plan. Add the three side lengths: 12 + 15 + 20 = 47 meters.

    The perimeter is 47 meters.

    Check your answer. To check this solution, start with the perimeter of 47 meters. If each side length is subtracted from this value, the result should be zero: 47 – 12 – 15 – 20 = 0, so this solution is checking.

  5. Read and understand the question. This question is looking for the side of a square when an expression for the sides and the perimeter is known.

     

    Make a plan. The perimeter is the distance around the object. Since the figure is a square, each of the sides are of equal length. Use 5x for the length of each of the four sides.

    Carry out the plan. Add the expression that represents each side, and set the value equal to 40. Then solve for x.

      5x + 5x + 5x + 5x = 40

    Combine like terms.

      20x = 40

    Divide each side by 20 to get x = 2. Substitute x = 2 into 5x to get the length of one side.

      5(2) = 10

    The length of one side is 10 units. Another way to solve this question is to use that fact that the figure is a square and the perimeter is 40. Divide 40 by 4 to get a side length of 10 units.

    Check your answer. To check this solution, add the four sides to be sure the perimeter is 40.

      10 + 10 + 10 + 10 = 40

    so this solution is checking.

  6. Read and understand the question. This question is looking for the length of the rectangle when the relationship between the length and the width is given, along with the perimeter.
  7. Make a plan. Use the relationship between the length and width to write let statements. Then, add the four sides together and set the equation equal to 80.

    Carry out the plan. The length is three times the width, so let w = width, and let 3w = length. The perimeter is w + 3w + w + 3w = 80. Simplify to get 8w = 80. Divide each side by 8 to get w = 10. The length is 3(10) = 30 meters.

    Check your answer. To check your solution, substitute w = 10 into the perimeter formula to make sure that the perimeter is equal to 80 meters.

    Since w = 10, 3w = 3(10) = 30. Adding the four sides becomes 10 + 30 + 10 + 30 = 80. This answer is checking.

  8. Read and understand the question. This question is looking for the perimeter of a regular pentagon.
  9. Make a plan. The perimeter is the distance around an object. A regular pentagon is a five-sided polygon where each side has the same measure. Each side of the fence is 35 meters long.

    Carry out the plan. Add the sides: 35 + 35 + 35 + 35 + 35, or 5 × 35 = 175.

    The perimeter is 175 meters.

    Check your answer. To check this solution, start with the perimeter of 175 meters. If each side length is subtracted from this value, the result should be zero.

      175 – 35 – 35 – 35 – 35 – 35 = 0

    so this solution is checking.

  10. Read and understand the question. This question is looking for the perimeter of a regular octagon.
  11. Make a plan. The perimeter is the distance around an object. A regular octagon is an eight-sided polygon where each side has the same measure.

    Each side is 20 cm.

    Carry out the plan. Add the sides: 20 + 20 + 20 + 20 + 20 + 20 + 20 + 20, or 8 × 20 = 160. The perimeter is 160 cm.

    Check your answer. To check this solution, start with the perimeter of 160 units. If each side length is subtracted from this value, the result should be zero.

      160 – 20 – 20 – 20 – 20 – 20 – 20 – 20 – 20 = 0

    so this solution is checking.

Add your own comment

Ask a Question

Have questions about this article or topic? Ask
Ask
150 Characters allowed