The number 642 is added to a 3-digit number 7x2 to give a 4 digit 13y4 which is exactly divisible by 11.
Find the value X*Y

• 7x2 + 642 =13y4
  And it is completely divisible by 11 so y would be 6 .
  If y is 6 then x would be 2 for sure
  Noe x*y = 6*2=12
• 8 years agoHelpfull: Yes(3) No(0)
• 2X2+642=13y4
  a number is divisble by means sum of digit of odd place-sum of digit of even place
  hence 1+y-3+7=y-6 hence y must be 6 becuse number is 4 digit
  so 7X2+642=1364
  7X2=1364-642
  7x2=722
  x=2 hence x*y=2*6=12
  
• 7 years agoHelpfull: Yes(1) No(0)
• 77
  13(X+4)4=13y4
  X+4=y
  Givrnx+4/11
  X=7 gives only 4 digit number
  S0,X+4=y
  Y=11
  X*y=77
• 5 years agoHelpfull: Yes(0) No(1)