Math Is Fun Forum

Non-titled

Guest

Parenthensis

Hey guys,
I've been struggling with this problem.
Insert parenthesis to make the statement true:
5-2.6-4+2=5

I can't really thinking of a strategy other than trail and error.
So, if you could help me and give a description of how you found the answer that'd be great !
Thanks in advance

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Parenthensis

Cześć!

Well, one sure way to get a definitive result is to go through all the possibilities, which are not many, since you just have to choose which operation gets performed before which. 4 operations means there are 4!=24 different orders to do the operations in. So, for example, you could label each operation with a number 1 through 4, then list out all the permutations of the sequence 1,2,3,4 and perform the operations in the order signified by each permutation. E.g., 3241 would mean you'd group them like 5-((2*(6-4))+2).

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thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: Parenthensis

|(5)(-2.6)|-(4)(+2)=5
The operation between parantheses is debatable though.

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