Question

PLZ help !!! can someone plz help me solve this question.

To register for online banking services at a local credit union, you need to select a four-digit
personal identification number, or pin code. The digits cannot be repeated. How many ways
are there to arrange four digits out of the numerals 0 through 9 to create a code?

Answer 1

[10 * 9 * 8 * 7] = 5040

Answer 2

(x)(x-1)(x-3) or 10*9*8*7=5040

Answer 3

is this how we do it ?
nᴾr = n! / (n - r)!
10ᴾ4 = 10! / (10 - 4)!
10ᴾ4 = (10*9*8*7*6*5*4*3*2*1) / ( 6*5*4*3*2*1)
10ᴾ4 = 3628800 / 720
10ᴾ4 = 5040

Answer 4

is 5040 the pin code ?
but its say no digit can be repeated right ? but in the answer 0 i repeated

Answer 5

5040

Answer 6

lets say x is the chosen digit.....you have 10 choices for the first one, if you take that out because it is unusable, you have 9 choices for the second, 8 for the third, etc....so the total number of combinations would be 5040

Answer 7

In the answer the digits can repeat

Answer 8

Because it's the number that many time 10 9 8 7 can be arranged

Answer 9

Many different times*

Answer 10

E.g. Code can 98710 or 87910 .... 5040 different codes

Answer 11

oh ok thank you so much i understand now. is the process i have written above the correct way to right it ?

Answer 12

Yes :)

Answer 13

ok thank you