Question

How many different six-digit decimal numbers can be formed where the first digit is a 1 or the last digit is a 5?

Answer 1

Answer:

10000 different numbers

Step-by-step explanation:

The numbers will have the form 1XXXX5, in this case, the order is important because 123465 is a different number to 123645. To know the total of differents decimal numbers, use the formula of permutation with repetition:

$n^r$

$n$ is the number of options, $n=10$, and $r$ the number of times you have to place a digit, $r=4$.

$10^4=10000$