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3rd grade

Unit 11: Lesson 2

Perimeter of polygons with missing side lengths
Math
3rd grade
Perimeter
Perimeter of polygons with missing side lengths
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Find a missing side length when given perimeter

CCSS.Math: 3.MD.D.8
Google Classroom

Problem

The perimeter of the figure is 31, start text, space, m, end text.
What is the length of the missing side?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
start text, m, end text
A four-sided figure with sides labeled as follows: 8 meters 6 meters, question mark meters, and 10 meters.
Stuck?
Stuck?