Question 198611
Here we go:
{{{a=40x}}} and {{{b=75x}}} where x=hours
If {{{a+b=460}}} then
{{{40x+75x=460}}}
Simplify and solve
{{{115x=460}}}
{{{x=4}}}
4 hours

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Anthony Allie
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http://arallie.webs.com/tutoring.htm