There is a five-digit number. The fifth digit is one fourth of the third digit and one half of the fourth digit. Third digit is one half of the first digit. Second digit is 5 more than the fifth digit. What is that 5-digit number? (6 marks)

• solution is 86421
  we can prove it as follows
  suppose number is pqrst, now
  t=(1/4)r=(1/2)s......(1),r=(1/2)p.....(2),q=t+5....(3)
  now from (1)4t=r=2s=k(suppose)....(4)
  from (2) 2r=p...(5)
  now(4)*2 then we get 8t=2r=4s=k(again some integer)....(6)
  from (5) and (6)
  8t=2r=4s=p=k.........(7)
  now we have to choose the value of k
  1)if choose k=0 then it is worthless number will be 00000(not a answer)
  2)for k=1 to 7 and for k=9 digits will be in fractions
  3)for k=8 we get p=8,s=2,r=4,t=1 and q=6
  and number is pqrst=86421
• 13 years agoHelpfull: Yes(4) No(1)
• 86421 or 12468 depending on which one is your first number.
• 13 years agoHelpfull: Yes(3) No(2)
• The five digit number is 86421.
• 13 years agoHelpfull: Yes(2) No(1)
• 87422
• 13 years agoHelpfull: Yes(0) No(3)
• 86421
  e can take only 1 as b=a+5,e=c/4,e=d/2
  substituting value of e in given condition,we get a=8,b=6,c=4,d=2,e=1.
  Hence 86421
• 13 years agoHelpfull: Yes(0) No(0)