# The 1st Digit is Half of 2nd | ATM Pin Puzzle | With Answer

Here is a brain teaser that is trending in all social media platforms & especially in WhatsApp. People are spending hours to find the correct solution for sharing in the groups.

Here we are providing the solution for this math puzzle with detailed steps on how to get the solution.

#### QUSETION

A house wife forgot her bank ‘ATM PIN’ which is a four digit number, but luckily she remembered some hints on how to recall this ‘PIN’

Here are some of the clues
1) The 1st digit is half of the 2nd
2) The sum of the 2nd and 3rd is 10
3) The 4th is equal to the 2nd plus 1
4) The sum of all the digits is 23

What is the ATM PIN ?

4829 is the ATM Pin

Explanation
Let The ATM Pin = 1000a + 100b + 10c + d
Equation 1: 2a = b (from 1st clue)
Equation 2: b + c = 10 (from 2nd clue)
Equation 3: d = b + 1 (from 3rd clue)
Equation 4: a + b + c + d = 23 (from 4th clue)

By Solving this we get,
From Equation 2 & 4 we get,
a + 10 + d = 23
=> a + d = 13
So let Equation 5: a + d = 13

From Equation 1 & 2 we get,
d = 2a + 1
So let Equation 6: d = 2a + 1

Solving Equation 5 & 6 we get,
a + 2a + 1 = 13
3a = 12
Therefore, a = 4

From Equation 1 we get, b = 8
From Equation 2 we get, c = 2
From Equation 3 we get, d = 9

So the code is : (1000×4) + (100×8) + (10×2) + 9
=> 4000 + 800 + 20 + 9
=> 4829