Missing Price
Math brain teasers require computations to solve.
When I went to the store, I purchased four items. The following shows the cost of three of the items:
$1.50
$3.00
$4.00
The line to the checkout was pretty long, so to quench my boredom I started playing with my pocket calculator while waiting.
I found out, to my surprise, that the four prices of the four items I purchased added to the same number as I got when I multiplied the four prices together.
What was the price of the fourth item?
HintAdd and multiply what you have already.
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Answer
The three prices add to 1.50 + 3.00 + 4.00 = $8.50.
The three prices multiply to 1.50 x 3.00 x 4.00 = $18.00.
You might be able to see that adding another $0.50 will take the total to $9.00, and multiplying by another $0.50 will take the product to $9.00 also, but the answer can also be found using algebra. Let's call the unknown price P:
1.50 + 3.00 + 4.00 + P = 1.50 x 3.00 x 4.00 x P
8.50 + P = 18.00 x P
8.50 = 18.00 x P  P
8.50 = 17.00 x P
8.50/17.00 = P
P = 0.50.
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Comments
SRB_1807
Mar 05, 2012
 Good one but pretty easy .... keep them coming ...cheers.... 
addspras
Mar 27, 2012
 like these easy fun ones..keep em coming! 
Babe
May 20, 2012
 No comment! 
castia123
May 20, 2012
 yeah it is easy 
HABS2933
May 20, 2012
 Nice and easy, perfect for a Sunday morning 
FatHead
May 21, 2012
 Not bad, but not much of a challenge, eh? 
edwardfalana
Jan 26, 2013
 Cool, but not much tasking. 
edwardfalana
Jan 26, 2013
 Cool, but not much tasking. 
raisin99
May 21, 2015
 simple, but at least got the juices flowing! 
auntiesis
May 21, 2015
 I got the answer in seconds without using a calculator or paper and pen. Pretty easy. I like math problems, but this one was too easy. 
JMac
May 25, 2015
 Thanks for the puzzle! It was fairly easy to just figure it out without any formulae, but your algebra work has me stumped. All is fine until you go from:
8.50 = 18.00 x P  P
to...
8.50 = 17.00 x P
How do you get to 17.00 when dropping off the " P"?
Jim 
dalfamnest
Jun 17, 2016
 The algebra approach is quite predictable. What would be interesting would be for solvers to explain HOW they did it in "a few seconds"! I enjoyed this puzzle, even though it is easy. 
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