Tom and Martin worked 9 hours this week.
These are their hourly wages:
Tom: $2.15
Martin: $2.50
This means that:
Tom earned 9 x $2.15 in wages, which is equal to $19.35.
Martin earned 9 x $2.50 in wages, which is equal to $22.50.
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Now, we've been told that Tom and Martin sold $360 worth
of meals but we were not told how much they received in tips.
For all intents and purposes, let's say that they received $n
in tips. 15% of $n in tips would be less than 20% of $n
in tips. Now, Martin is already going to be receiving a higher
wage, and the fact that he is going to be receiving 20% of
$n in tips compounds the logical conclusion that at the end
of the week, he'd be leaving work with more money than Tom.
Answer:
Martin made more money than Tom.