SOLUTION: the ratio of the present ages of a and b is 11:4 and 15 years ago it was 8:1. if 5 years ago the ratio of the ages of b and c was 3:2,then what is c's present age ?

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: the ratio of the present ages of a and b is 11:4 and 15 years ago it was 8:1. if 5 years ago the ratio of the ages of b and c was 3:2,then what is c's present age ?      Log On


   

Question 867128: the ratio of the present ages of a and b is 11:4 and 15 years ago it was 8:1. if 5 years ago the ratio of the ages of b and c was 3:2,then what is c's present age ?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

a%2Fb+=+11%2F4  a = (11/4)b

%28+%2811%2F4%29b-15%29%2F%28b-15%29+=+8%2F1

 8(b-15) = (11/4)b-15

 32(b-15) = 11b - 60

 32b - 32*15 = 11b - 60

       21b = 420

         b = 20

%2820-5%29%2F%28c-5%29+=+3%2F2

     30 = 3(c-5)

     30 = 3c - 15

     45 = 3c

      c = 15, present age