An online store randomly assigns shoppers a confirmation code after making a purchase. the confirmation code consists of 4 letters followed by 3 digits. within the confirmation code, letters can be used only once but digits can be repeated. how many different confirmation codes are possible?

A. 14,950,000
B. 5,311,735
C. 358,800,800
D. 358,800

C. 358,800,800

Step-by-step explanation:

Total digitrs ( from 0 to 9 ) = 10

Total letter ( from a to z ) = 26

To make the code , we require 4 letters followed by 3 digits .

If letter can be used once ( i.e. repetition is not allowed) , then the number of ways to arrange this sequence of letters =  [By using Permutation]

But repetition is allowed for digits , so number of ways to arrnge 3 digits =

Now , the total number of ways tio make the code = 358800  x 1000

=358,800 ,000

Hence, the correct option is C. 358,800,800.

the answer   is 200

step-by-step explanation:

this is a problem about poisson probabilities.   i don't know if you've

already studied poisson distributions, or if you have a place to look

to read more about the subject.  

here's how you can see a poisson distribution coming.   when there are

a lot of events that may happen at any time (or any place), and when

you're counting how many of them happen at a particular time (or a

particular place), and each event is independent of the others, then

the result is a poisson distribution.   this is roughly true for the

chocolate chips; one chip being in a cookie has only a small effect on

the probability that another chip will be in the cookie.

once you know you have a poisson distribution, you know a lot.   there

is only one parameter to a poisson distribution, so if you know the

mean, you know everything.   the form of the distribution is

  probability of n chips = {[e^(-x)]*(x^n)} / (n! )