A bicycle store costs 4200$ per month to operate. The store pays an average of $45 per bike. The average selling price of each bicycle is $165
. How many bicycles must the store sell each month to break even?
Let x be the number of bicycles the store must sell each month to break even.
The total cost to operate the store is $4200.
The profit from each bicycle sold is ($165 - $45) = $120.
The total profit from selling x bicycles is $120x.
To break even, the total profit must be equal to the total cost.
So, 120x = 4200.
Hence, x = 4200/120 = <<4200/120=35>>35.
Therefore, the store must sell 35 bicycles each month to break even. Answer: \boxed{35}.