Question

How many more 4 digit even numbers than 4 digit odd numbers can be formed using only digits from the set (0,1,6)? Pls show working. Thx

Answer 1

• 4 digit even numbers
  
  
  `2\cdot3^2\cdot2=36`
  
  first digit – any of 2 digits except 0 (a number can't start with 0)
  second and third digit – any of all 3
  fourth digit – any of 2 even digits
  
• 4 digit odd numbers
  
  
  `2\cdot3^2=18`
  
  first, second and third digit – as in the first case
  fourth digit – the only 1 possible odd digit

`36-18=18`

So, 18 more.