9398
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2012-09-14T15:27:37
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If the pattern shown is continued, what number will appear directly below $400$?<br></br>
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$1$<br></br>
$2$ $3$ $4$<br></br>
$5$ $6$ $7$ $8$ $9$<br></br>
$10$ $11$ $12$ $13$ $14$ $15$ $16$<br></br>
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If you liked this problem, <a href="/7529">here is an NRICH task</a> which challenges you to use similar mathematical ideas.<br></br>
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The number at the end of the $n$th row is $n^{2}$,<br></br>
so $400$ will lie at the end of the $20$th row.<br></br>
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The row below will end in $21^{2}$, i.e. $441$<br></br>
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So the number directly below $400$ will be $440$.<br></br>
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<mdoxml version="1.0">Patterns and Sequences - Stage 3 Short Problems UKMT 2003-04 p31 Q16</mdoxml>
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Weekly Problem 42 - 2012
If the pattern continued, what number will appear directly below 400?
Secondary Mapping Document
DisplayCabinet
Secondary Mapping Document
Patterns and sequences LS