Question 1108701
.
Walt made an extra $7000 last year from a part-time job. He invested part of the money at 6% and the rest at 8%. 
He made a total of $480 in interest. How much was invested at 8%? 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


<pre>
<U>Interest at 8%</U>  +  <U>interest at 6%</U> = <U>total interest</U>


0.08*x          +  0.06*(7000-x)  = 480


0.08x + 420 - 0.06x = 480

0.02x = 480 - 420  ====>  0.02x = 60  ====>  x [ {{{60/0.02}}} = {{{6000/2}}} = 3000.


<U>Answer</U>.  $3000 was invested at 8%.


<U>Check</U>.   0.08*3000 + 0.06*(7000-3000) = 480 dollars.   ! Correct !
</pre>

---------------
To see many other similar solved problems on investment, look into the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/coordinate/lessons/Using-systems-of-equations-to-solve-problems-on-investment.lesson>Using systems of equations to solve problems on investment</A>

in this site.


You will find there different approaches (using one equation or a system of two equations in two unknowns), as well as 
different methods of solution to the equations (Substitution, Elimination).


Also, &nbsp;you have this free of charge online textbook in ALGEBRA-I in this site

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-I - YOUR ONLINE TEXTBOOK</A>.


The referred lesson is the part of this online textbook under the topic "<U>Systems of two linear equations in two unknowns</U>".



Save the link to this online textbook together with its description


Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson


to your archive and use it when it is needed.