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I divided 9 by 60 (for 60 seconds in an hour) and that came out to $0.15$. Then I do $0.15x = 1$ which is $6.666...$. Does that mean it takes those many seconds for him to make a dollar?

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Maybe better to use 60 minutes in an hour, not seconds. – GEdgar Dec 7 '13 at 22:00
If he makes $\$9$ in an hour, he makes $\$1$ in 1/9th of an hour (assuming his pay is linear, I suppose). – doppz Dec 7 '13 at 22:00
Does that seem plausible? That it takes him 6.6 seconds to make \$1, but that it takes him one hour to make \$9? Math is also about common sense. – Najib Idrissi Dec 7 '13 at 22:20
up vote 1 down vote accepted

If Bob works for $h$ hours then he gets paid $9 \times h$ dollars. You need to work out how long it takes for him to earn $\$1$, which amounts to solving the equation $$9 \times h = 1$$ to find $h$. This gives you the number of hours. To find out how many minutes this is, multiply by $60$.

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Try writing $$ \frac{9\text{ dollars}}{1\text{ hour}}=\frac{1\text{ dollar}}{x\text{ hours}} $$ and solve for $x$. $x$ is measured in hours, so multiply by $60$ to get to minutes, and once more by $60$ to get to seconds.

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1 hour= 3600 seconds

3600/9= 400 seconds=6 minutes and 40 seconds

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