Putting it all together:
,

• Use one cut strip from striped and blue border fabric - each 1 1/2 x 15" .
  Cut in 3 lengths - 5" each.
• Join striped fabric - blue - striped fabric - make 1 set -press seam allowance open.
  Join blue fabric - striped - blue fabric - make 1 set - press seam allowance open.
• Cut 3 units - 1 1/2" wide - from each set.
  Diagrams 1 and 2
• Join as shown in diagram. - Diagram 3
• Join 2 blocks.

 Diagram 1

Diagram 2

Diagram 3

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