Trade slides both traders along their own worth lines to the crossing, and past it both would lose
Sam’s gain
Joe’s gain
Loss to both
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
Granola bars per bottle
0
10
20
30
40
40
30
20
10
0
Sam →
← Joe
Bottles of water — 40 in all
Price settles at 0.60 a bottle
Sam’s personal worth
Joe’s personal worth
No trades yet
At the 20-bottle start: the next bottle is worth 0.98 to Sam, 0.22 to Joe
Their worths still differ — the next trade creates 0.76 bars of gain
Drag either brass dot forward along its line until the two worths meet —
then keep dragging past the crossing to see why the trading stops there (arrow keys work too).
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