Operations Management help needed. please check your work, provide explanation if possible. if it's right I'll give you a like.

Frank's TVs wants to increase capacity by adding a new machine. The firm is considering proposals from vendor A and vendor B. The fixed costs for machine A are $54,000 and for machine B,$32,000. The variable cost for A is $107 per unit and for B,$230. The revenue generated by the TVs manufactured on these machines is $500 per unit. What is the crossover (in units) between machine A and machine B (to the nearest whole number)