Question

Elijah forgot his pass code for a certain website. He knows it is made up of 3 digits and no digit can be repeated. If he randomly chooses 3 different digits, what is the probability that he chooses his pass code?
(Points : 3)
Option A: 1/2160
Option B:1/720
Option C: 1/240
Option D: 1/20

Answer 1

hmmmm What do you think

Answer 2

no clue

Answer 3

i am gonna say option D

Answer 4

Can you give me the formula please?

Answer 5

Well, there are 25 letters in the English language that Elijah could pick from. There are also 10 numbers, 1-9 and 0 that could possibly fit there.

Answer 6

he can only choose 3 digits, no letters

Answer 7

Unless otherwise proved, don't guess the answer.

Answer 8

Then it would be reduced to 10 options without the 25 letters.

Answer 9

okay, so whats the formula?

Answer 10

There are 10 possible options for the first digit, 9 for the second, and 8 for the third.
10 x 9 x 8 would give you what you are looking for.

Answer 11

@_Squish explained it perfectly

Answer 12

Okay thank you! <33

Answer 13

Sure thing.

Answer 14

Wait so how does that give me a fraction?

Answer 15

@_Squish o-o ;-;

Answer 16

@rishavraj T-T

Answer 17

its asking probability thts why.... -_- @LeilaJudeh

Answer 18

Okay...? So whats the formula for probability?

Answer 19

(no of favorable cases)/(total no of cases)
-_-
no of favorable cases = 1

Answer 20

why one?

Answer 21

WAIT NVM

Answer 22

Im so condused rish -_-

Answer 23

*confused

Answer 24

lmao rish shutup xDD Stick to math

Answer 25

theres only one combination....i mean hmmmm only one combination of digits would be the password....... thts why favorable case = 1

Answer 26

1 / 720 .

Answer 27

@LeilaJudeh got it ?????

Answer 28

and thats why I said nvm. But totalnumber of cases is 10? cant be. THIS IS WHY IM CONFUSED.

Squish. I wanna know how to solve it lmao

Answer 29

total no of cases = 720

Answer 30

Where did you get 720 from?

Answer 31

There is no "formula" to find this, as most of it can be solved through common sense. If there are three digits and 10 of them are available to you that you can only use once, this would mean that the first digit would have 10 options available to you. After that, 9 since there has been one option already used. Then, 8 since you've used a second option. And so on and so forth. However, you only had three digits, therefore 10 x 9 x 8 will give you 720. BUT, there's only ONE password that he'll be using. Therefore, 1 / 720 is your answer.

Answer 32

Okay I got it now. THANK YOU SQUISH <33

see rish that is how you explain

Answer 33

@LeilaJudeh okay M'am

Answer 34

Sure thing.