The sign for average is done with the dominant hand in a
"flat-hand" shape and the non-dominant hand in an "open-B-hand"
shape. The dominant hand taps the non-dominant hand twice at
the midpoint between the non-dominant hand's thumb and fingertips.
(The non-dominant hand doesn't move in this sign.)
Also see: APPROXIMATELY
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American Sign Language (ASL) online at American Sign Language University ™
ASL resources by Lifeprint.com © Dr. William Vicars