SOLUTION: six years ago the ratio of kunal and sagar age was 6:5,hence 4 years later the ratio becomes 11:10.Then find the present age of kunal?

Algebra ->  Customizable Word Problem Solvers  -> Age -> SOLUTION: six years ago the ratio of kunal and sagar age was 6:5,hence 4 years later the ratio becomes 11:10.Then find the present age of kunal?      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1007732: six years ago the ratio of kunal and sagar age was 6:5,hence 4 years later the ratio becomes 11:10.Then find the present age of kunal?
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
We can solve this using two proportions, which will give us two equations to solve from...we have (using k and s for their ages NOW)...
%28k-6%29%2F%28s-6%29+=+6%2F5 and %28k%2B4%29+%2F+%28s%2B4%29+=+11%2F10
If we cross-multiply these we get
5(k-6) = 6(s-6)
5k - 30 = 6s - 36
5k - 6s = -6
and
10(k+4) = 11(s+4)
10k + 40 = 11s + 44
10k - 11s = 4
Double the first one and subtract
10k - 11s = 4
-(10k - 12s = -12)
----------------
s = 16
k = 18