A two digit number is 4 times to its sum of digits , when 9 is added to the number, the digits will get reversed. Then what is that number?

• The Answer is 12
  From the above, the following equation can be arrived:
  (10x+y)-(10y+x)=9
  solving we get x-y=-1
  There are so many possibilities of different values of x,y vix
  (1,2),(2,3)(3,4),(4,5)(5,6),(6,7),(8,9)
  But from the above possibilities, the condition satsfies is the number 12
• 12 years agoHelpfull: Yes(5) No(1)
• two digit no will start from 10
  addition 1 + 0 = 1 * 4 = 4+9=13
  1 + 1 = 2 * 4 = 8+9=17
  1 + 2 = 3 * 4 = 12+9=21 hence ans is 12...
• 10 years agoHelpfull: Yes(3) No(0)
• let no will be 10x+y
  1st condition :
  10x+y = 4x+4Y
  so, 2x-y = 0 ......(1)
  2nd condition :
  10x+y+9 = 10y+x
  so, x-y = -1 .......(2)
  solve (1) & (2)
  x=1 $ y=2
  so, 10x+y = 12
  so no is 12...
• 9 years agoHelpfull: Yes(3) No(0)