Question 732523
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Sally is 10 years older than Tim. In 8 years, the sum of their ages will be 40. 
Determine how old Sally and Tim are now.
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        The solution to this problem in the post by @lynnlo is incorrect.

        I came to bring a correct solution.



<pre>
Let x be the Tim's age.

Then the Sally's age is (x+10) years.


In 8 years, Tim's age is (x+8) years, while Sally's age is ((x+10)+8) = (x+18) years.


In 8 years, the sum of their ages will be 40 - so we write this equation

    (x+8) + (x+18) = 40.


Simplify and find 'x'

    2x + 26 = 40,

    2x = 40 - 26 = 14,

     x           = 14/2 = 7.


Thus Tim is 7 years old now;  Sally is 7+10 = 17 years old now.   <<<---===  <U>ANSWER</U>


<U>CHECK</U>.  (7+8) + (17+8) = 15 + 25 = 40.   ! correct !
</pre>

Solved correctly.