40296

1 a)
Step 1:Ask yourself what you know about the problem.
Step 2:Looking at the second diagram, the length is 13cm.
Step 3:You can fit that diagram at the top and bottom of the first diagram.
Step 4:Take away 2x13 from the first diagram because you placed the second diagram twice in the first diagram.
Step 5:Then you have the middle rectangle left.Taking away 2x13 which equals 26, you can figure out the length of the middle rectangle because you have 7cm left.The length of the middle rectangle is 7cm.
Step 6:If you add all the 7cm lengths, it equals 21.Then you figure out the widths.You have 12cm to split between 4 widths which eqauls 3cm.
Step 7:Each length of the rectangle equals 7cm and each width equals 3cm.
Step 8:The perimeter of the rectangle equals 7+3+7+3=20cm.