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textcopyright{} 2009 $-$ 2018 David Nguyen \
All rights reserved.

    This work is not to be  distributed and/or modified without licensse.

This content has been tailored by the author over his years of training the best mathematical minds. Problems in the booklet provides a wide array of mathematics flavours, enhance problem solving and thinking ways for young learners.

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 99 32 11 88 48 01hspace{2em}9 9 8 6 5 4 %1
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First edition:  & May 2010 \
Second impression, with minor extensions & January 2011 \
Third impression, with minor extensions & May 2016
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Institute of Mathematics\
Vietnam

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