Can anyone solve this step by step?
Answers
Given :-
402 : One number is correct and well placed
415 : One number is correct but placed wrongly.
204 : Two numbers are correct but placed wrongly.
938 : Nothing is correct.
890 : One number is correct but is placed wrongly.
To find :-
The codé which can unlock.
Let us look at the numbers one by one.
482 :-
The hint given for this is that one number is correct and well placed.
By the observations we can conclude that the digits of the number can be either 4, 8 or 2.
415 :-
The hint given is that one number is correct but placed wrongly.
Hence we can conclude that the digits of the number can be 4, 1 or 5.
There are high chances of one of the digits to be 4 as it's repeating again.
204 :-
Two numbers are correct but wrongly placed.
Therefore the digits can be 2,0 or 4.
There's more chances of 4 being one of the digits now.
938 :-
Nothing is correct
So the digits of the number can't be 9,3 or 8.
890 :-
One number is correct but placed wrongly.
By the above observation we know that the digits can't be 8 or 9
Hence one of the digits is surely 0 but it can't be in the one's place.
This shortens our options,
In number 482 we now know that the digit can't be 8, so we are left with digits 4 and 2
In the number 415 we noticed that the digit 4 was repeated, hence the second digit of the number can be 4 but 4 can't be in the hundred's place.
In number 204 two numbers were correct but placed wrong.
By the observations we have found out that 4 and 0 are two of them
Since 0 is can't be in the one's place (given in hint after number 890), 0 has to be in the hundred's place.
If we look at the number 482, the hint said that one number was correct and well placed, hence 2 is the third number, as from number 482, we know that 1 number is correctly placed. Since in number 415 and 204 we get to know that 4 is one of the digits of the number, we can conclude that the codé is 042