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Puzzling Profits: Newsletter Challenge (July 2020)

Posted June 30, 2020 5:01 PM
Pathfinder Tags: challenge question profit

This month's IEEE GlobalSpec Newsletter Challenge is:

Lance sells Eddy a bike for $100. A few days later, Eddy discovers some mechanical issues and sells it back to Lance for $80. Ever the opportunist, Lance then sells the same bike to Bernard for $90.

What is Lance's total profit?

Hint: this is something of a trick question, with three possible answers. Can you guess them all?

And the answer is:

As stated above, there are several interpretations of this puzzle.

1. The original cost of the bike is unknown. What is known is that Lance bought it back for $80 and solid it for $90, so he definitely made a $10 profit.

2. Lance originally sold his bike for $100 and then bought it back for $80, so he made $20. The next transaction is irrelevant because the bike's original is unknown.

3. After Lance made his original $20 profit from Eddy's sale, he sold it to Bernard for $10 more than he just paid for it, so his total profit is $30.

This is essentially a semantic problem in that the correct answer depends on a personal definition of "total profit." Only by knowing the bike's original value can an exact profit be ascertained.

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#1

Re: Puzzling Profits: Newsletter Challenge (July 2020)

06/30/2020 5:26 PM

Profit?

Vacant the original cost of this bike, profit is incalculable.

One of the three possible answers is $110.00, if zero cost is presumed.

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#10
In reply to #1

Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/07/2020 11:36 AM

GA

Then there are the other unknown costs of storage, fees, utilities, repairs (did he really resell a known defective bike?), etc.

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#2

Re: Puzzling Profits: Newsletter Challenge (July 2020)

06/30/2020 5:34 PM

After selling to Eddy, Lance has $100

After buying it back from Eddy, Lance has $20

After selling to Bernard, Lance has $110

His profit depends on what the bike was worth, what Lance originally paid for it. (If he stole it, his first profit was $100.)

On the second transaction, he lost $20.

On the third transaction, he made $30.

If X is the value of the bike, total profit is X - 100 - 20 + 30 or X - 90

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#3

Re: Puzzling Profits: Newsletter Challenge (July 2020)

06/30/2020 6:04 PM

Fair market value for the bike must be established...since it last sold for $90, that is the established market value...So the profit is $20...

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#4
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Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/01/2020 6:02 PM

I like your thinking. GA.

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#5

Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/02/2020 12:34 AM

Lance -> Eddy, X = original cost, profit = $100 – X or X - $100 = loss.

Eddy -> Lance, profit = $120 – X or (X+$20) - $100 = loss or profit or even?

Lance -> Bernard, (same bike = no repairs?) profit $130 – X or (X+$30) -$100. as above.

Answer, Lance total profit has three possibilities (1) profit, (2) loss, (3) even.

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#6

Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/02/2020 1:34 AM

Apart from the normal profit made on a sale of $100/- he made an additional profit of $20/- when he got it returned at a depreciated price of $80/-

Taking for granted that the mechanical issues were sorted out without any capital expenses, by the second sale he made a profit of $10/-

Thus the total profit made was $30/- Plus the original profit (Secret and hence not divulged in the riddle)

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#7

Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/02/2020 5:28 AM

Once the three possible profits are calculated it then depends on what Lance's local tax man extracts from Lance's lucrative sideline in selling bikes.

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#8

Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/02/2020 9:08 AM

Lance makes nothing, only bernard and eddy make a profit. Lance, after receiving the bike back from eddy due to serious mechanical issues, then sells bike to bernard without disclosing them. Bernard subsequently sustains an injury after the front wheel falls off and his lawyer, with the aid of Eddie's disposition, successfully sue lance for every nickel he's got.

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#9

Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/02/2020 10:54 AM

Doorman’s got it as succinctly correct as possible. Ignoring the time value of money, Lance’s profit from two sales is $100 minus what the bike originally cost him (which we don’t know from the narrative and was the first sale), plus $10 from the second rip-off sale of a defective product.

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#11

Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/09/2020 3:21 PM

Good choice of name for a cheat selling a bike!!!

Funnily enough his name was Lance Edward.... so maybe the first two transactions were irrelevant to the final answer, or some way to create a tax write off.

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Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/10/2020 1:32 PM

Maybe Eddie bought this bike from Lance in which case it was a steal.

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#13

Re: Puzzling Profits: Newsletter Challenge (July 2020)

07/24/2020 11:17 AM

Answer is posted.

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