To use an automated teller machine at a certain bank, you must enter a 3-digit code, using the digits 1 dash 9. how many 3-digit codes are possible if repetition of digits is permitted?

729 , 3- digit codes are possible

Step-by-step explanation:

To use an automated teller machine at a certain​ bank, you must enter a 3​-digit ​code, using the digits 1 dash 9.

We need a 3 digit code using digits 1 to 9

so total of 9 digits are used

also repetition of digits are permitted

In a 3 digit code, first digit can be any number from 0 to 9

so 9 possible numbers for first digit.

since repetition is allowed so second and third digit also have any number between 0 to 9

3 digit code

,   ,

9 possibilities for each place

---9--- ,  9--- , 9

9 *9 *9 = 729

so 729 , 3- digit codes are possible

1 x=22.52

2: 65/39=604+39x

65x-39x=604

26x=604

x=604/26

×=23.23