Poisson Distribution--Help

Questions:

Vehicles arrive at an intersection at a rate of 10 per minute. A traffic light cycle lasts 45 seconds. What is the distribution of the number of vehicles that arrive per cycle?

For the Poisson distribution with mean 7.5.

I understand the excel function - "POISSON(x, mean, true / false)" can be used to solve it.

But how can i write the VBA code to express it?? Help.