A certain number is added to each of a pair of numbers which are in the ratio 4:7. The sum of the resulting numbers is 75 and their ratio(taken in the same order as mentioned above) is 8:17.What is the number added?

• Ans : -12
  
  Let x be the certain number & y be the ratio constant such that initially the numbers are 4y and 7y
  
  (x+4y)+(x+7y)=75 => 2x+11y=75 ....(1)
  
  Also (x+4y)/(x+7y)=8/17
  => 9x+12y=0 or 3x+4y=0 .... (2)
  
  Solving 1 and 2
  
  x=-12 and y=9
  
  Hence the number added was (-12)
  
  
• 11 years agoHelpfull: Yes(53) No(5)
• The sum of the resulting numbers is 75 and their ratio(taken in the same order as mentioned above) is 8:17.
  
  only possible set of numbers such that The sum of the resulting numbers is 75 and their ratio(taken in the same order as mentioned above) is 8:17
  is
  24,51.
  Difference between numbers = 51-24 = 27
  Only numbers which are in ratio of 4:7 having a difference of 27 are 36 and 63.
  
  so number added in 36 to make it 24 is (-12).
• 11 years agoHelpfull: Yes(14) No(2)
• 8x+17x=75,x=3;
  put x in 1st ratio yu will get 4x:7x
  4x+y+7x+y=75,
  12+21+2y=75,
  y=21,is the answer..!1
  
• 11 years agoHelpfull: Yes(4) No(3)