In: Statistics and Probability
An e-retailing company assigns an ID to online orders received. Order ID starts with 3-digit number, followed by four letters of alphabet.
a) How many unique order IDs could be generated?
b) What is the probability that first order is assigned an ID where sum of 3 digits equals 4? For instance, consider order ID “123 ABCD” with sum of three digits equals 1+2+3 = 6.