tag:blogger.com,1999:blog-3776665703590564248.post536192696057155280..comments2021-01-20T19:37:18.727-05:00Comments on Return To Excellence: Two-Train Timing QuizReturnToExcellence.nethttp://www.blogger.com/profile/18149859814999976879noreply@blogger.comBlogger18125tag:blogger.com,1999:blog-3776665703590564248.post-81351988917807210932017-10-26T00:02:29.846-04:002017-10-26T00:02:29.846-04:00Darn I was so close, thanks Doug, if I get problem...Darn I was so close, thanks Doug, if I get problems with letters instead of number I am lost at the gate.JRnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-89161817076677346552017-10-25T19:36:08.171-04:002017-10-25T19:36:08.171-04:00Imagine two perfectly parallel train tracks with t...Imagine two perfectly parallel train tracks with the front of the engines lined up going in the opposite direction @ the speeds specified. The two trains are pulling away from this initial spot @ 90 miles per hour (30 mph + 60 mph). The second spot of concern is when the end of the last cars of each train will be in alignment on the parallel tracks which brings the length of the trains into play (1.25 miles + 0.25 miles = 1.5 miles). So the problem boils down to how long does it take something going 90 miles an hour to go 1.5 miles. 1.5/90 = 0.01667 hours which some people got but forgot to convert to minutes. Multiple 0.01667 hours times 60 minutes per hour & you get 1 minute. You can also recognize that 1.5/90 is 1/60 of an hour or 1 minute.RTEnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-81160841237283287392017-10-25T19:33:53.875-04:002017-10-25T19:33:53.875-04:00I am still getting .0166 min. to pass, will wait f...I am still getting .0166 min. to pass, will wait for your answer<br />JRnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-43185087962450608712017-10-17T19:47:26.712-04:002017-10-17T19:47:26.712-04:00You have many principles correct but I think you a...You have many principles correct but I think you are making it too complicated.<br /><br />Do use minutes although 7,920 = 1.5 miles is correct<br /><br />Go to your second solution that uses miles<br /><br />90 miles/hour X 60 minutes does not equal 5,400 minutes it equals 5,400 miles-minutes/hour – units do not workout to anything useable<br /><br />Work 1.5 miles & 90 miles per hour & see how long it takes the trains to pass – & you have it – put the answer in minutes<br /><br />Will provide my solution after you make one more try.<br />RTEnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-20267004992607248072017-10-17T19:34:55.788-04:002017-10-17T19:34:55.788-04:00OK lets try this for the quiz. For the trains to p...OK lets try this for the quiz. For the trains to pass each other will take 1.466 minutes. <br /><br />7920 ‘ of train<br />MPH of trains is equal to a head on collision at 90 MPH,<br />60 min. in 1 hour X 90 = 5400 min. <br />7920’ * 5400 min. = 1.466 minutes to pass each other. <br /><br />Is the best I can come up with , is different then my first try.<br /><br />1.25 + .25 = 1.5 miles of train.<br />90 MPH x 60 min. = 5400 min. <br />7920’ * 5400 = 1.466 min. to pass<br /><br />There is still a gray area in my head just can not clear it.<br /><br />JRnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-77016545592482693152017-10-16T22:34:08.261-04:002017-10-16T22:34:08.261-04:00The kids came up with 1 mile! Oops, my mistake, th...The kids came up with 1 mile! Oops, my mistake, they said 1 minute!SRKnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-80132141742437431892017-10-12T22:37:14.625-04:002017-10-12T22:37:14.625-04:00Doug,
Since the length of both trains is 1.5 mile...Doug,<br /><br />Since the length of both trains is 1.5 miles & using the formula D = R * T to find T;<br /><br />60 * T + 30 * T = 1.5<br /><br />90 * T = 1.5 <br /><br /> T = 1.5/90 = 1/60 = 1 minute to completely pass each other.<br /><br />JORnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-40399141413114614552017-10-11T19:11:44.653-04:002017-10-11T19:11:44.653-04:00You must be doing something right because 0.166 is...You must be doing something right because 0.166 is correct but not in minutes. 0.166 minutes is less than 10 seconds so the trains would really be flying. Look again @ your units & I think you have it.RTEnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-52813081737091650422017-10-11T19:07:20.984-04:002017-10-11T19:07:20.984-04:00Will take a stab at it. If am right will show how....Will take a stab at it. If am right will show how.<br /><br />.166 minutes to pass each other.<br />JRnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-73458712526170918352017-10-11T19:04:30.812-04:002017-10-11T19:04:30.812-04:00Since the trains are traveling in opposite directi...Since the trains are traveling in opposite direction to each other, the end speed is the combination of the two speeds., i.e. 60 + 30 = 90 m.p.h. = 90/60 = 1.5 m.p.min.<br /><br />The length of the trains are 1.25 miles + 0.25 miles = 1.5 miles and that is the length the two trains have to travel for last cars of the two freight trains to clear each other.<br /><br />Therefore time taken to travel distance mentioned above is 1.5 m.p.min/1.5 m. = 1 min.<br />PBnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-25630443221225862422017-10-10T23:21:25.553-04:002017-10-10T23:21:25.553-04:00Another fun quiz - thanks!Another fun quiz - thanks!PRunoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-73542175697060785772017-10-10T23:17:54.402-04:002017-10-10T23:17:54.402-04:00This one is hard..not sure i got it to be honest ...This one is hard..not sure i got it to be honest , but here is how i did it. <br /><br />One train is moving 60 MPH which is one mile per minute. The other train is 1 .25 miles long so...if the bigger train was not moving it would take 1.5 minutes to totally pass the larger train (1.25 miles plus the .25 miles of the other train). But the other train is also moving at 30 mph so we have to factor that in. This is where i get lost. I am guessing that at 30 MPH it would take the larger train 30 seconds to pass the other train.(30 mph equals 1/2 mile a minute and .25 miles in 30 seconds) So i would reduce the total time by 30 seconds and I come up with exactly one minute.<br />HowKnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-42764902106387692072017-10-10T19:22:12.666-04:002017-10-10T19:22:12.666-04:00How did you get it?How did you get it?RTEnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-30282917811017061642017-10-10T19:21:21.233-04:002017-10-10T19:21:21.233-04:00Doug - My answer is 1 minute.
Doug - My answer is 1 minute.<br />PBnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-56395392648901352802017-10-09T22:40:27.443-04:002017-10-09T22:40:27.443-04:00BullseyeBullseyeRTEnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-10701101014063228812017-10-09T22:39:31.634-04:002017-10-09T22:39:31.634-04:00Hi Doug!
Here's my stab at the Train Quiz.
Ho...Hi Doug! <br />Here's my stab at the Train Quiz.<br />Hope all is well with you.<br /><br />Answer: 1 minute<br /> <br />Long Train : Length = 1.25 mi, speed = 30 mph<br />Short Train: Length = .25 mi, speed = 60 mph<br /> <br />This is equivalent to:<br /><br />Long Train : Length = 1.25 mi, speed = 90 mph<br /><br />Short Train: Length = .25 mi, speed = 0 mph (standing still)<br /><br />The rear of the Long Train has to travel the length of both trains (1.25 + .25) = 1.5 mi<br />1.5 mi / 90 mph = 1 minute<br /><br />Another way to look at it:<br /><br /><br />At start<br /> Long Train (30mph): |---.25---|---.25---|---.25---|---.25---|---.25à|<br />Short Train (60 mph): |<--.25---|<br /> <br />After 1 minute<br />Long Train travels ½ mile: |---.25---|---.25---|---.25---|---.25---|---.25à|<br />Short Train travels 1 mile: |<--.25---|<br />PRunoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-27576486644338484272017-10-09T16:24:25.319-04:002017-10-09T16:24:25.319-04:00I had a friend help me with the quiz. Still don&#...I had a friend help me with the quiz. Still don't get it. Help!!!tlgnoreply@blogger.comtag:blogger.com,1999:blog-3776665703590564248.post-26306372906867490862017-10-08T22:32:01.787-04:002017-10-08T22:32:01.787-04:00Sorry could not complete quiz. At school was neve...Sorry could not complete quiz. At school was never good at these type questionsThe Historiannoreply@blogger.com