A foundry receives an order for three custom-designed castings. The customer will pay $30,000 for each of three good castings. The customer will accept neither fewer nor more than three castings. It will cost $10,000 to produce each casting. Each casting is produced independently; the probability of a casting being good is estimated to be 0.90. write the cost Revenue and profit equations. How many castings should be produced?

PLEASE IN THE QUESTION THERE IS ((((3 good castings)))) in the third line NOT 3 ! full answer pleasssse