Question 1131150
r, pay rate for the carpenter
r-6, pay rate for apprentice


x, time that carpenter worked
x+10, time that apprentice worked



{{{system(rx=720,(r-6)(x+10)=720)}}}
Solve the system, especially for r.



Another Way:

<pre>
                  PAY RATE        TIME       PAY

Carpenter            r            720/r      720

Apprentice          r-6         720/(r-6)    720

DIFFERENCE                       10
</pre>
{{{highlight_green(720/(r-6)-720/r=10)}}}--------solve for r.