A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.
What is the sum of the three digits?

• There r only 4 prime numbers which can form 3 digit number are: 2,3,5,7
  2 & 3 r the only digits whose product can produce a single 3rd digit
  as 2*5=10,3*5=15....first two digits must be either 2 or 3 i.e. 22, 23, 32 or 33 which means that there are four possible numbers - 224, 236, 326 and 339. it is also given that the difference between its reverse and itself is 396. Only 236 satisfies this condition
  so the number will be 236 and also 632-236=396.
• 11 years agoHelpfull: Yes(8) No(0)
• 11 is the sum of the three digits.
  The number is 236. Unit digit(6)=product of other two digits(2*3);2 & 3 are prime.
  Difference between its reverse(632) and itself(236) = 396. So answer is 2+3+6=11.
• 13 years agoHelpfull: Yes(7) No(0)
• 236
  
  Diff of 396 means First and last digit should differ by 4 and first digit ( prime also) should be a factor of last digit. Prime digits are 2,3,5,7. Only possible combination is 236 which satisfies all conditions.
  
• 13 years agoHelpfull: Yes(4) No(2)
• 236 as 632-236= 396 and 2,3 are prime numbers such that 2*3=6
• 13 years agoHelpfull: Yes(2) No(2)
• *1 is not a prime number hence 155 is not possible but 236 is the right answer
• 13 years agoHelpfull: Yes(2) No(0)
• Number is 236 and sum of digits = 2+3+6=11
• 13 years agoHelpfull: Yes(1) No(0)
• There r only 4 prime numbers which can form 3 digit number are: 2,3,5,7
  2 & 3 r the only digits whose product can produce a single 3rd digit i.e. 6
  as 2*5=10,3*5=15....
  so the number will be 236 and also 632-236=396.
• 12 years agoHelpfull: Yes(1) No(2)
• 155:bcoz 551-155=396
  236:bcoz 632-236=396
  hence answer is 155 or 236
• 13 years agoHelpfull: Yes(0) No(4)
• @mohd Anas...1 is not prime no. dude..
• 11 years agoHelpfull: Yes(0) No(1)