<PRE><B>Question 1206391</B>
&lt;br&gt;
The incorrect solution from one of the other tutors is because he has Ron working the additional 35.5 minutes instead of Tony.  (I made the same mistake the first time I set the problem up....)&lt;br&gt;
Here is a different setup and solution.&lt;br&gt;
Ron takes 2/3 as much time as Tony to trim a certain number of trees.  Then, recognizing that 71 minutes is exactly twice 35 minutes and 30 seconds = 35.5 minutes....&lt;br&gt;
Let 2x = # of trees Tony trims in 35.5 minutes
Then 3x = # of trees Ron trims in 35.5 minutes&lt;br&gt;
Together in 71 minutes the number of trees they trim is 2(2x+3x) = 10x.&lt;br&gt;
The number of trees Tony alone trims in the additional 35.5 minutes is 2x.&lt;br&gt;
The total number of trees they trim is then 10x+2x = 12x.&lt;br&gt;
The number of trees they trim all together is 10, so 12x = 10, and x = 5/6.&lt;br&gt;
Now the number of trees Tony trims in 35.5 minutes is 3x = 3(5/6) = 5/2 = 2.5, so the number of minutes it takes Tony to trim 10 trees is 4(35.5) = 142 minutes.&lt;br&gt;
ANSWER: 142 minutes.&lt;br&gt;
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