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-   -   Math Problem (http://archives2.twoplustwo.com/showthread.php?t=24190)

Jim Brier 11-16-2002 05:49 AM

Math Problem
 
Hal gives Tom as many raffle tickets as Tom first had and Gary as many as Gary first had. Then Tom gives Hal and Gary as many tickets as they then had. Finally, Gary gives Tom and Hal as many tickets as they currently had. Hal, Tom, and Gary end up with 40 tickets each. How many tickets did Hal, Tom, and Gary each have to start with?

pudley4 11-16-2002 11:43 AM

Re: Math Problem
 
Work it backwards:

At the end, G=40, T=40, H=40

If Gary gave Tom and Hal enough tickets to double their holdings, then before this transaction, T=40/2=20, H=40/2=20, G=40+20+20=80

If Tom gave tickets to Hal and Gary, then before he did, H=10, G=40, T=70

If Hal gave tickets to Gary and Tom, then before he did, G=20, T=35, H=65


SunTzu68 11-16-2002 04:30 PM

Re: Math Problem
 
Hal=70, Tom=40, Gary=10. I'm not sure how the previous player got 65+35+20 to equal 120 (3 x 40), but his methodology was essentially correct.

Jim Brier 11-17-2002 05:09 AM

Answer
 
The answer is Hal originally had 65 tickets, Tom originally had 35 tickets, and Gary originally had 20 tickets. Pudley's approach is better than mine. I worked the problem from the "front end" which is far more cumbersome.

Jim Brier 11-17-2002 05:10 AM

65+35+20 =120 and is correct. (n/t)
 
(n/t)

11-17-2002 10:05 AM

Re: Answer
 
65+35+20 does indeed work out to 120, I apologize for my previous post. However, it is still not the right answer. Let me work it through, and maybe someone can show me where my mistake is.

Hal Tom Gary
70 40 10
Hal than doubles Tom's and Gary's tickets making it:
20 80 20
Tom than doubles Hal's and Gary's tickets making it:
40 40 40- The right ending point.

If we were to use the other set of starting numbers it works out this way:
Hal Tom Gary
65 35 20
10 70 40
20 20 80-which is not the 40, 40, 40 that was what they ended with. So the correct answer has to be 70, 40, and 10.

Let me say that I also used the long approach to this, creating an algebra equation to solve it. Pudley's approach was much better. I gave this problem to my 10 yo step-son in the car and he solved it in less than 5 minutes (it took me longer to explain the problem to him than it did for him to solve it.) I think they teach math in a much better way than they did when we were in school, using common sense and estimating.

SunTzu68 11-17-2002 10:09 AM

Re: Math Problem
 
65+35+20 does indeed work out to 120, I apologize for my previous post. However, it is still not the right answer. Let me work it through, and maybe someone can show me where my mistake is.

Hal Tom Gary
70 40 10
Hal than doubles Tom's and Gary's tickets making it:
20 80 20
Tom than doubles Hal's and Gary's tickets making it:
40 40 40- The right ending point.

If we were to use the other set of starting numbers it works out this way:
Hal Tom Gary
65 35 20
10 70 40
20 20 80-which is not the 40, 40, 40 that was what they ended with. So the correct answer has to be 70, 40, and 10.

Let me say that I also used the long approach to this, creating an algebra equation to solve it. Pudley's approach was much better. I gave this problem to my 10 yo step-son in the car and he solved it in less than 5 minutes (it took me longer to explain the problem to him than it did for him to solve it.) I think they teach math in a much better way than they did when we were in school, using common sense and estimating.

SunTzu68 11-17-2002 10:46 AM

Re: Math Problem
 
OOOOOOOOOOOps, my mistake........I only had the first two trades...........

Jim Brier 11-17-2002 06:53 PM

You Only Did The First Two Trades! (n/t)
 
(n/t)

Jim Brier 11-17-2002 06:54 PM

Same Mistake As Anonymous Above (n/t)
 
(n/t)


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