tag:blogger.com,1999:blog-2514352312859447561.post4773604018668065878..comments2021-05-01T06:26:54.321-04:00Comments on Bad Data, Bad!: Wednesday Brain Teaser 3-20-13bs kinghttp://www.blogger.com/profile/02871717971078952304noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-2514352312859447561.post-52482639225397628172013-03-22T12:14:26.546-04:002013-03-22T12:14:26.546-04:00Sweet. SJ March, I'm handing this to my 15 yea...Sweet. SJ March, I'm handing this to my 15 year old. heh. heh. heh.<br /><br />I followed the process until you looked at factorization. I understand your conclusion but not the process there. Don't tell me. I guess I will have to have my 15 year old explain it to me. <br /><br />They say that teaching someone else helps you learn. heh. heh. heh. Dubbahdeehttps://www.blogger.com/profile/00075702513873912334noreply@blogger.comtag:blogger.com,1999:blog-2514352312859447561.post-75199036322118965372013-03-21T17:10:10.167-04:002013-03-21T17:10:10.167-04:00Mathematics is not my strong point with the except...Mathematics is not my strong point with the exception of giving birth to a mathematician. My initial thought was "But... it was 2525 wasn't it?"Donna B.https://www.blogger.com/profile/16771075314473811594noreply@blogger.comtag:blogger.com,1999:blog-2514352312859447561.post-90065184062992848242013-03-21T13:57:16.613-04:002013-03-21T13:57:16.613-04:00Your ethics in recusing yourself are admirable.Your ethics in recusing yourself are admirable.bs kinghttps://www.blogger.com/profile/02871717971078952304noreply@blogger.comtag:blogger.com,1999:blog-2514352312859447561.post-29490265976229428242013-03-21T13:54:19.228-04:002013-03-21T13:54:19.228-04:00Full credit for showing your work.Full credit for showing your work.bs kinghttps://www.blogger.com/profile/02871717971078952304noreply@blogger.comtag:blogger.com,1999:blog-2514352312859447561.post-9965191062098485792013-03-21T10:49:54.532-04:002013-03-21T10:49:54.532-04:00Let's see...2520 is divisible by 9. (The digit...Let's see...2520 is divisible by 9. (The digits sum to a value divisible by 9.) <br />And divisible by 10, 5. (Last digit is zero.)<br />And divisible by 8. (Since 520 is divisible by 8.)<br />And divisible by 7. (A little harder...used <a href="http://math.about.com/library/bldivide.htm" rel="nofollow">this algorithm</a>. Also got 2520/7 = 360.)<br /><br />Divisibility by 9 implies divisibility by 3. <br />Divisibility by 8 implies divisibility by 2 and 4. <br />Both of the above imply divisibility by 6.<br /><br />Thus, 2520 is divisible by 2, 3, 4, 5, 6, 7, 8, 9, and 10. (And divisible by 1.)<br /><br />Looking at the factorization, 2520 = 5(7)8(9) = 2^3(3^2)5(7), so there shouldn't be a smaller integer divisible by all integers in the range [1,2,...10].SJhttps://www.blogger.com/profile/12043843405366080460noreply@blogger.comtag:blogger.com,1999:blog-2514352312859447561.post-76145070409044600932013-03-21T09:30:27.884-04:002013-03-21T09:30:27.884-04:00Nobody got that one yet? It isn't fair for me...Nobody got that one yet? It isn't fair for me to answer--I assigned that problem (the inverse) when homeschooling math, so I recognize it.jameshttps://www.blogger.com/profile/01792036361407527304noreply@blogger.com