40
Or at least that what my calculator says.
Let

, where

and let

be any real constant.
Given this definition of scalar multiplication, we can see right away that there is no identity element

such that

because
111.1 is the answer to the question
Ahmad = 1/6
Barry = 1/2
Tara = 1 - 1/6 - 1/2 = 1/3
1/3 of the seashells = 76
3/3 of the seashells = 76 x 3
3/3 of the seashells = 228
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Answer: They had 228 seashells altogether.
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