If you have cut your strips correctly and you are sewing two 2" strips to the 3" strip... the only way you can end up with 5 1/2" is if your seams aren't 1/4".
Lay out your strips...you should have a total of 7" before seams.
After your first seam your strip should measure 4 1/2".
When you sew your last strip on the block should measure 6".
Sorry the pics didn't come out in the order sent.
After sewing your last seam, you should end up with a 6" block.
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You should have 7" total with your 3 strips.
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After the first seam you will have a 4 1/2" strip.
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