Question 126645
hi there,
this is what i figured out .. i think i pretty self explainitory , hope it helps

<table>
<tr><td>passenger train</td><td>270 mph</td></tr>
<tr><td>freight train</td><td>210 mph</td></tr>
<tr><td>difference</td><td>60  mph</td></tr>
</table>

to build up this difference they had to ride for 60/12 = 5 hours and therefore
the passenger train's speed 	= 270 / 5 = 54 mph
the freight train's speed	= 210 / 5 = 42 mph<br>
and the difference in speed = 54 - 42 > 12 mph