The Cassette Recorder

There was a man who went to the mall where he bought 3 pairs of red socks and 3 pairs of white socks.Another man who had already bought 3 pairs of red socks and 3 pairs of white socks came back to return his 6 pairs. They were both blind.

As they were walking, they bumped into each other. All the socks scattered around the floor, but each pair remained held together by a rubber band. Nobody helped them pick the socks up, but in 3 minutes they both had 3 pairs of red, and 3 pairs of white.

How is that possible if they are blind?

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