Question 1187186
<pre>
             SPEEDS         TIMES             DISTANCE

PLANE        r              1200/r              1200

CAR          r-100           400/(r-100)         400
</pre>
The two times were described as equal.

{{{1200/r=400/(r-100)}}}




{{{3/r=1/(r-100)}}}

{{{3(r-100)=r}}}

{{{3r-300=r}}}

{{{2r=300}}}

{{{highlight(r=150)}}}

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