1.13
Mental Math
• 3(1000s)+7(100s)=4(10s)+9(1s)
• 9 (10,000s)=8(1,000s)+5(100s)=4(10s)+3(1s)=
• 5(1,000,000s)=9(100,000s)+6(10,000s)+3(1,000s)+7(
100s)+3(10s)+9(1s)=
Math message
• Math journal page 32
• Find the perimeter of the square shown at the
top of journal page 32.Convert your answer to
inches
• Remember perimeter is the length of a
boundary of a closed shape. Trace around the
edges of the square on page 32. How did you
find the perimeter?
• How did you convert the answer to inches?
Objective: you will identify a rule or formal for finding the perimeter of a rectangle
• Look at the rectangle on Problem 1 on journal
page 32. Point to longer side and identify that
inside as length. The side that runs
perpendicular to the length is the width.
• What is the length of the rectangle? Width?
Perimeter?
• How can you generate a rule that can be used
to find the perimeter of any rectangle?
Review
• Math antics
• Perimeter
• Perimeter rap
Make a poster that demonstrates how
to find the perimeter of an object
• You will be finding several objects in the class
to measure and find the perimeter of.
• First, name the protocols you will be using in
class to “move around the class”.
• Next, using a ruler or straight edge, draw the
object and solve the problem(perimeter)
• Make sure your paper is neat and the answer
is CORRECT.