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<p>When is the value of the product $$(1 + {1 \over 2})(1 + {1 \over 3})(1 + {1 \over 4})...(1 + {1 \over n})$$ equal to an integer?</p>
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If you liked this problem, <a href="http://nrich.maths.org/708">here is an NRICH task</a> which challenges you to use similar mathematical ideas. </p></mdoxml>
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<p>The product is $${3 \over 2}\times{4 \over
3}\times{5 \over 4}\times
\cdots\times{(n+1) \over n}$$ which will reduce to
$${(n+1) \over 2}$$i.e. it is an integer only when n is odd.</p>
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Weekly Problem 46 - 2011
This product has n terms in it. Can you evaluate find out when it is equal to an integer?
Secondary Mapping Document
Number operations and calculation methods