Why in this case lambda = 1/2.9 but not =2.9? can you please briefly go through when will lambda is equal to x and when will lamda is equal to 1/x?

so when will lamda equal to 1/x and when will lamda equal to x? in this case lambda is equal to 1/2.9?

3. Game World, a video game arcade at Tanglewood Mall, has just installed a new virtual reality battle game. It requires exactly 2.7 minute to play. Customers arrive on average every 2.9 minutes (Poisson distributed) to play the game. How long will the line of customers waiting to play the game be and how long on average must a customer wait