Suppose you invest $10,400 in equipment to manufacture a new board game. each game costs $2.65 to manufacture and sells for $20. how many games must you sell to break even?

599.42 games
To answer this question, you need to calculate the revenue for every game sold first. The calculation would be:
Revenue= sell cost - manufacture cost= $20-$2.65= $17.35/game.

Break even is the point when the game manufacturing cost(equipment cost included) is covered by the revenue you got. Then the calculation would be:

total game cost= revenue per game * number of game sold
$10400= number of game sold * $17.35
number of game sold= 10400/17.35=  599.42 games