BdMO National 2013: Primary 5

Discussion on Bangladesh Mathematical Olympiad (BdMO) National
BdMO
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Joined: Tue Jan 18, 2011 1:31 pm

BdMO National 2013: Primary 5

Unread post by BdMO » Fri Jan 10, 2014 1:15 am

For any two numbers $x$ and $y$, the absolute value of $x$ and $y$ is defined as $|x-y| = $ difference between the numbers $x$ and $y$. For example, $|5-2| = 3, |3-9| = 6$. Let $a_1, a_2, a_3, \cdots , a_n$ be a sequence of numbers such that each term in the sequence is larger than the previous term.

Let $S = |a_1 - a_2| + |a_2 - a_3|+ \cdots + |a_{n-1} - a_n|$. What is the minimum number of numbers that you need to know from the sequence in order to find $S$?

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samiul_samin
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Joined: Sat Dec 09, 2017 1:32 pm

Re: BdMO National 2013: Primary 5

Unread post by samiul_samin » Sat Feb 17, 2018 10:52 pm

Hint
Use numberline and read the question twice
Answer
$\fbox 2$
Inspired by Afser_Adil_Olin

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