Serial numbers for a product are to be made using 4 letters followed by 4 digits. the letters are to be taken from the first 9 letters of the alphabet, with no repeats. the digits are to be taken from 0-9 with no repeats. How many serial numbers can be generated?

15,240,960 serial numbers

Step-by-step explanation:

Since no repeats are allowed and the order matters, the number of possible serial numbers is given by the product of the permutation of 4 out of 9 letters by the permutation of 4 out of 10 numbers:

There are 15,240,960 ways to generate a serial number.

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,