
ExtravagantDream
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lol you crazy mo'fo'. I hope you didnt write those all out by hand hehe

Anno
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I think excel was of big help on that one....

JssMthrFcknChrst
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Re: So you think you know your math huh... [Re: Anno]
#1478094  04/21/03 03:06 AM (18 years, 29 days ago) 


VB


chodamunky
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Re: So you think you know your math huh... [Re: Lana]
#1485569  04/23/03 11:23 AM (18 years, 27 days ago) 


These are the final and CORRECT answers to you problem. In Finite math you learn exactly this and there are two possible answers to your question.
1) If you can only use each digit once (0 to 9) , there are 9*9*8*7 = 4536 combinations (assuming first digit cannot be zero since 0234 = 234 and thats only a 3 digit number.)
2) If you can use any digit multiple times, then 9*10*10*10 = 9000 combinations, again, assuming the first digit cannot be zero.
Hope that helps, looks like you owe your friend some grub

trypyamine
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Does anyone know some interesting math or science problems? [Re: ExtravagantDream]
#1504088  04/29/03 01:15 PM (18 years, 21 days ago) 


Does anyone know some interesting math or science problems? Here's an easy little test I found on another web forum.
Problems 17 must be done compleatly in your head or no credit!
1. Your given three identical thermos bottles, A,B, and C. A contains 100 deg water dyed red, B contains 20 deg water dyed blue, and C is empty. Empty container D fits easily into any thermos and has perfectly conducting walls. Without mixing the red with blue water, can you heat the blue water to a temp above the red water with the aid of container D. (0 points if you get this correct, minus 3 points if wrong).
2. Given an 8 liter flask, a 13 liter flask and a tap, how do you measure 1 liter? (0 points if correct, minus 3 if you cant figure this out within 5 minutes)
3. Two cars set out at the same time going from A to B, a distance of 100 miles. They both follow the same route and travel at different, but uniform speeds of an integral number of MPH. The difference in there speeds is a prime number of MPH. After they have been driving for 2 hours, the distance of the slower car from A is 5 times that of the faster car from B. What are the two cars speeds? (1 point if correct, minus 1 point if wrong/cant solve within 10 minutes)
4. You walk up an escalator at a rate of 1 step per second and get to the top in 20 seconds. The next day you walk up it at 2 steps per sec and get to the top in 32 steps. How many steps are there? (1 point if correct, minus 1 point if wrong/cant solve within 10 minutes)
5. Two hot rodders compeat in a race. Each acellerates at a uniform rate from a standing start. Al covers the last quarter in 3 seconds, Bob covers the last third in 4 seconds. Who won? (1 point if correct, minus 2 if wrong/cant solve in 5 minutes)
6. The time on your watch is off. Comparing it to an accurate clock, you notice that the every 65 minutes, the hour hand and the minute hand are together. Does your watch gain or lose, and how much per hour? (1 point if correct, minus 1 point if wrong/cant solve within 10 minutes)
7. In a cirtain community there are 100married couples. 2/3 of the husbands who are taller than thir wives are also heavier and 3/4 of the husbands who are hevier than their wives are also taller. If there are 120 wives who are taller and heavier than their husbands, how many husbands are taller and heavier than there wives? (1 point if correct, minus 1 point if wrong/cant solve)
8. 2 guys are walking towards eachother alongside a railway. A train overtakes the first guy in 20 sec, than 10 minutes latermeets the other guy comming in the opposite direction of the train . It than overtakes him in 18 seconds. How much longer after the tain passes the second man will they meet? (1 point if correct, minus 1 point if wrong/cant solve)
9. Two duelers with a 50% acurracy take turns shooting at each other.What are the odds in favor of the man who shoots first? (1 point if correct, minus 1 if wrong/cant solve it)
10. 5 equal size circles are incribed in a pentagon with length of edge 1. They are the largest that will fit. What is the radius of the largest cricle that will fit in the center (give frist 5 decimals. A calculator may be used.) (1 points if correct, minus 1 point if wrong/cant solve it)

ExtravagantDream
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Re: Does anyone know some interesting math or science problems? [Re: trypyamine]
#1504545  04/29/03 03:15 PM (18 years, 21 days ago) 


I could answer a few but some make no sense.
1. is this F or C? not that it really matters.. but still how can you make the cool one hotter than the hot without applying outside heat or cooling the hot one. Fill A(red water) into D and put into B(blue) to average the two and have equal temps then let D (red water) further cool in air?
2. this one is easy
3. integral = integer?? If so the only answer I could get was assuming 2 as a prime number
4. This problem is totally retared.. it confuses you by using the word "step" in two different meanings. step as in a step you take to move and step as in a phyical object.
5. I think I did this one right.. but its more of a guess then anything else. a true answer would take two integrals.. which i cant do in my head while keeping all the info seperate.
6. Think I got this one
7. Sounds like a fucked up community to me
8. too many variabls to solve for.. I think you can only do this by assuming both people are walking at the same speed
9. easy
10. I dont even know what that is saying So what are the answers.. I really like doing these kinda of problems... but they really have to be written well
Edited by ExtravagantDream (04/29/03 03:19 PM)

trypyamine
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Registered: 04/02/03
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Re: Does anyone know some interesting math or science problems? [Re: ExtravagantDream]
#1504855  04/29/03 04:55 PM (18 years, 21 days ago) 


" integral = integer?? " yes
"This problem is totally retared.. it confuses you by using the word "step" in two different meanings. step as in a step you take to move and step as in a phyical object" The question is how many physical steps are there, or how many steps would it take if the elevator was broken.
You can do #5 without integrals.
"too many variabls to solve for.. I think you can only do this by assuming both people are walking at the same speed" You sure?
Ill post the answers in a day so more people have a chance to try them.

ExtravagantDream
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Registered: 10/24/02
Posts: 1,271
Loc: Somewhere in the Local Su...
Last seen: 13 years, 11 months

Re: Does anyone know some interesting math or science problems? [Re: trypyamine]
#1508078  04/30/03 04:56 PM (18 years, 20 days ago) 


I know what the question is.. "how many steps are there" obviously has to be a physical quantity.
"4. You walk up an escalator at a rate of 1 step (stride) per second and get to the top in 20 seconds. The next day you walk up it at 2 steps (stair or stride?) per sec and get to the top in 32 steps(stride or stair?)."

trypyamine
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Last seen: 17 years, 9 months

Re: Does anyone know some interesting math or science problems? [Re: ExtravagantDream]
#1508591  04/30/03 07:21 PM (18 years, 20 days ago) 


That would be "stairs" not strid, i think. Here are the answers. 1. Yes. fill D with blue water, submerge D in A until the two liquids are the same temp. Dump contents of D into C. Repeat this process untill B is empty. 2. Everyone should be able to figure this out. 3. 2s=5(1002f), s=2505f, fs=6f250 this must be two because its prime, f=126/3=42, s=40 4. n20r=20, n16r=36, n=100 5. Bob wins 6. On an accurate clock, the hans are together every 65+5/11 minutes. So every 65 minutes your watch gains 5/11 minutes, so every hour your watch gains (5/11)(60/65)=60/143 minutes. 7. (2/3)T=(3/4)H= the number of husbands who are taller and heavier, T=(9/8)H, T+H(2/3)T= number of husbands who are taller and/or heaveir, 100TH+(2/3)T=1000T(8/9)T+(2/3)T=1000(11/9)T=120, T=720, (2/3)T=180. 8. From the train's point of veiw let A and B be the speeds of the two guys.A/B=5/9. 5/9*620+5/9t=t, t=775s. 9. The first mans odds are 0.5+0.5*0.5*0.5+0.5*0.5*0.5*0.5*0.5+...=2/3 10. 0.28591
#10 is the most difficult.

ExtravagantDream
Beacon in theDarkness
Registered: 10/24/02
Posts: 1,271
Loc: Somewhere in the Local Su...
Last seen: 13 years, 11 months

Re: Does anyone know some interesting math or science problems? [Re: trypyamine]
#1508730  04/30/03 08:20 PM (18 years, 20 days ago) 


hmm.. im too lazy to check all of this for technicalities right now.. are these questions and anwers from a book or website? Mind if I know where? thanks

