7132 /www/nrich/html/content/id/7132/ 1 2011-02-01T00:00:01 <?xml version="1.0" encoding="UTF-8"?> <mdoxml version="1.0"><p><br></br> The product of four different positive integers is 100. What is the sum of these four integers?<br></br> <br></br> <br></br> If you liked this problem, <a href="http://nrich.maths.org/1862&amp;part=">here is an NRICH task</a> which challenges you to use similar mathematical ideas.<br></br> <br></br>  </p></mdoxml> <?xml version="1.0" encoding="UTF-8"?> <mdoxml version="1.0"><br></br> Since $100=2\times2\times5\times5$, the only possible product of four <span style="font-style: italic;">different</span> positive integers which equals $100$ is $1\times2\times5\times10$. The sum of these integers is $1+2+5+10 = 18$.<br></br>  <br></br>  <br></br></mdoxml> 2 3 0 0 1 0 0 Weekly Problem 38 - 2010 Calculations and Numerical Methods Mental calculation strategies Numbers and the Number System Integers Numbers and the Number System Factors and multiples Numbers and the Number System Prime factors