Question

Each book registered in the library of congress must have an ISBN code number. For an ISBN number the form D-DD-DDDDDD-D, where D represents a digit from 0-9, how many different ISBN numbers are possible if repetition of digits is allowed?

Answer 1

sum 1 help pls

Answer 2

idk

Answer 3

Because they're in different spots

Answer 4

what

Answer 5

An ISBN is printed on the lower portion of the back cover of a book above the bar code and on the copyright page.

Answer 6

@AZ

Answer 7

idk

Answer 8

@Astrid1

Answer 9

how many D's are there?

Since we can repeat the digits

and the only digits we have are 0-9 which is 10 numbers
0, 1, 2, 3, 4, 5, 6, 7, 8 and 9

then that means each blank has the possibility of being those 10 numbers

and so you write 10 in each blank and then multiply it across

Answer 10

so 10^10?

Answer 11

you got it!

Answer 12

bet thank you

Answer 13

you're welcome!