Question 1004999
>>Ken is 6 years older then Sue, who is 6 years older then Betty, 
who is 6 years older than Jason.<< 
<pre>
A little thinking about the statement above will tell you that 
Ken is 18 years older than Jason.

So {{{K = J + 18}}}
</pre>
>>Jason's age is half of Ken's age,<<
<pre>
{{{J = expr(1/2)K}}}

So we have the system of equations:

{{{system(K=J+18,J=expr(1/2)K)}}}

Since the question is
</pre>
>>how old is Jason?<<
<pre>
We substitute J+18 for K in {{{J=expr(1/2)K}}}

{{{J=expr(1/2)K}}}
{{{J=expr(1/2)(J+18))}}}

Multiply both sides by 2 to clear the fraction:

{{{2J=J+18}}}

Subtract J from both sides:

{{{J=18}}}, so Jason is 18.

Checking the words:
</pre>
>>Ken is 6 years older then Sue, who is 6 years older then Betty, 
who is 6 years older than Jason. Jason's age is half of Ken's age.<<
<pre>
Betty is 6 years older than Jason, so Betty is 24.
Sue is 6 years older than Betty, so Sue is 30.
Ken is 6 years older than Sue, so Ken is 36.
And indeed, Jason's age, which is 18 is half of Ken's age, 
which is 36.
 
Edwin</pre>