Question

A woman forgot her bank ATM PIN but she was able to recall some of the pin.

1)the 1st digit is half of the 2nd pin
2)the sum of 2nd and 3rd is equal to 10
3)the 4th is equal to the 2nd plus 1
4)the sum of all digits is 23
show workings please
what is the ATM digit?

Answer 1

The PIN is 4829

Explanation:

let s take 4 numbers a b c and d

the PIN is abcd

we know that

(1) a = b/2

(2) b+c=10

(3) d=b+1

(4) a+b+c+d=23

from (2) c = 10 - b

from (3) d = b + 1

so (4) gives

b/2 + b + 10 - b + b +1 = 23

so

3/2 b = 23 -11 = 12

b = 12*2/3 = 8

so d = 9

c = 10-8=2

and a = 4

so the PIN is 4829

thank you