# Can someone answer this IQ question for me? **URL:** \ **Category:** Factual Questions\ **Created:** [September 4, 2002, 4:11pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973 "2002-09-04T16:11:14Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 5, 2017, 4:41pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/21 "2017-11-05T16:41:23Z")
> [@winlanch](#): > > The answer is 1000 because it is a perfect square. In what number system? ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [November 5, 2017, 4:48pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/22 "2017-11-05T16:48:43Z")
> [@winlanch](#): > > The answer is 1000 because it is a perfect square. Congrats, you just gave an incorrect answer to a 15 year old thread! ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [November 5, 2017, 6:02pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/23 "2017-11-05T18:02:31Z")
> [@beowulff](#): > > In what number system? Base 4, duh! Or Base 9! Or Hex! Or base 25! (Sensing a pattern?) But definitely not base 10. I think our new friend forgot a zero and is thinking of 100^2, which is 10,000 and not 1,000. ---
**Author:** ![JoseB](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/joseb/32/1530_2.png) [@JoseB](https://boards.straightdope.com/u/JoseB)\ **Post date:** [November 5, 2017, 7:43pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/24 "2017-11-05T19:43:01Z")
> [@Sephic](#): > > I just don’t get it. I’ve asked around, but they don’t get it either. > > John likes 400 but not 300; he likes 100 but not 99; he likes 2500 but not 2400. Which does he like? > > 900 > 1000 > 1100 > 1200 > Extra points if you can tell me where I got it from 😉 Without reading the rest of the thread: he likes 900 because he likes square numbers and, of those presented, 900 is the only square (30^2) ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [November 6, 2017, 4:29pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/25 "2017-11-06T16:29:47Z")
> [@Darren\_Garrison](#): > > Congrats, you just gave an incorrect answer to a 15 year old thread! Well yes, but at least now after 15 years we finally know who’s not getting into Mensa. 😃 Agree with the poster up-thread who so long ago said that far too many of these things are really tests of “who thinks most like the test author” rather than tests of IQ or knowledge. For best results it’s very, very important to not have much more or less IQ than the test writer. Also to not have much more or less education than the test writer. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [November 6, 2017, 4:51pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/26 "2017-11-06T16:51:31Z")
If the test writer leaves Salt Lake City going west at 500 MPH, and you leave Beijing going south at negative 9000 miles per hour, what are the chances you will pass the test? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 6, 2017, 5:11pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/27 "2017-11-06T17:11:20Z")
> [@LSLGuy](#): > > Well yes, but at least now after 15 years we finally know who’s not getting into Mensa. 😃 > > Agree with the poster up-thread who so long ago said that far too many of these things are really tests of “who thinks most like the test author” rather than tests of IQ or knowledge. > > For best results it’s very, very important to not have much more or less IQ than the test writer. Also to not have much more or less education than the test writer. I remember taking a test a long time ago in which one of the questions was "which of these metals is not like the others: Gold, Aluminum, Silver, Iron " I realized that the answer they wanted was “Gold,” because of it’s color, but the answer could have also been “Iron,” because it was the only one of the four that was ferromagnetic. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [November 6, 2017, 5:25pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/28 "2017-11-06T17:25:12Z")
> [@beowulff](#): > > I remember taking a test a long time ago in which one of the questions was "which of these metals is not like the others: Gold, Aluminum, Silver, Iron " I realized that the answer they wanted was “Gold,” because of it’s color, but the answer could have also been “Iron,” because it was the only one of the four that was ferromagnetic. Also, aluminum is the only one of those four that is not a transition metal. ---
**Author:** ![DrCube](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@DrCube](https://boards.straightdope.com/u/DrCube)\ **Post date:** [November 6, 2017, 5:25pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/29 "2017-11-06T17:25:34Z")
> [@beowulff](#): > > I remember taking a test a long time ago in which one of the questions was "which of these metals is not like the others: Gold, Aluminum, Silver, Iron " I realized that the answer they wanted was “Gold,” because of it’s color, but the answer could have also been “Iron,” because it was the only one of the four that was ferromagnetic. Aluminum, because it’s the only one whose chemical symbol matches the name of the element in English. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [November 6, 2017, 5:26pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/30 "2017-11-06T17:26:45Z")
> [@DrCube](#): > > Aluminum, because it’s the only one whose chemical symbol matches the name of the element in English. Oh, that’s another good one. I actually like that answer better than “gold, because of its color.” Do we actually know the answer the test maker expected? ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [November 6, 2017, 6:06pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/31 "2017-11-06T18:06:16Z")
If there’s more than one answer that can be plausibly reasoned into, then it’s a bad question. Those get tossed in more-rigorous environments than the sort of Facebook link that the OP question apparently comes from. ---
**Author:** ![nate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nate/32/13085_2.png) [@nate](https://boards.straightdope.com/u/nate)\ **Post date:** [November 6, 2017, 6:13pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/32 "2017-11-06T18:13:15Z")
I have a different take on the answer. I think the answer is 1200. It is based on the combination of the question and answer choices. Like most of these type questions, it doesn’t require you to be clever with math but clever with patterns. John likes a number but does not like the result if the first digit is decremented by 1. So looking at the possible solutions, you can eliminate all but 1200. He wouldn’t like 900 because 1000 is also a choice, wouldn’t like 1000 because 1100 is also a choice, and wouldn’t like 1100 because 1200 is also a choice. Therefore, only 1200 could be the answer. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [November 6, 2017, 6:40pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/33 "2017-11-06T18:40:31Z")
> [@beowulff](#): > > I remember taking a test a long time ago in which one of the questions was "which of these metals is not like the others: Gold, Aluminum, Silver, Iron " I realized that the answer they wanted was “Gold,” because of it’s color, but the answer could have also been “Iron,” because it was the only one of the four that was ferromagnetic. > [@pulykamell](#): > > Also, aluminum is the only one of those four that is not a transition metal. > [@DrCube](#): > > Aluminum, because it’s the only one whose chemical symbol matches the name of the element in English. OK, so we’ve established that gold, iron, and aluminum are each different from the other three in at least one plausible way. Can we establish a plausible way that silver differs from the other three? Chemistry is by far my weakest area. And if we can’t, doesn’t that prove that silver is the correct answer because, unlike the other three, there’s no plausible way to partition the four metals into silver vs the others. 😃 :smack: Stupid / ignorant / blinkered test authors cost me a lot of frustration in school. When I am Emperor they will pay the price for their foolishness. _Bwah ha ha ha_!!! ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [November 6, 2017, 6:46pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/34 "2017-11-06T18:46:16Z")
Another one for iron is that iron is the only one of those four whose chemical symbol does not begin with “A.” ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [November 6, 2017, 7:14pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/35 "2017-11-06T19:14:10Z")
Iron is the only one which has never been a precious metal; aluminium extraction methods were historically poor, and it was worth more than gold until the 1800s. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [November 6, 2017, 7:17pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/36 "2017-11-06T19:17:37Z")
The weird thing is, I really _don’t_ know which one of these is the most likely answer that the test taker intended. I’m not sure I like the answer “gold.” I would personally bet on “aluminum,” for the reasons given by **DrCube**. That kind of seems more like the type of answer a test maker would be going for, at least in my experience. ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [November 6, 2017, 7:26pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/37 "2017-11-06T19:26:15Z")
> [@LSLGuy](#): > > OK, so we’ve established that gold, iron, and aluminum are each different from the other three in at least one plausible way. > > Can we establish a plausible way that silver differs from the other three? Much higher electrical conductivity. > [@](#): > > Stupid / ignorant / blinkered test authors cost me a lot of frustration in school. When I am Emperor they will pay the price for their foolishness. _Bwah ha ha ha_!!! Unclear, multi-answerable, or simply wrong questions are the constant curse of trivia players, too. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [November 6, 2017, 8:16pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/38 "2017-11-06T20:16:40Z")
> [@beowulff](#): > > In what number system? In base 4, base 9, base 16, base 25,…, also base 900. 1000 in base b is b^3 and hence is a square if and only if b is. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [November 6, 2017, 8:32pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/39 "2017-11-06T20:32:35Z")
> [@ElvisL1ves](#): > > Much higher electrical conductivity. > … There are lots of ways to simply pick “Which substance of the four has the most extreme value for property X?”. In fact there are as many ways as there are identifiable properties X. A problem with that approach is that while silver has the highest conductivity iron has the lowest. Which extreme is more “natural” to be interested in? So for N properties we now have 2N ways to select the most interesting. That seems to me to be uninteresting. So what we need is a property where one substance is a clear outlier and the other three substances are nearly indistinguishable on that same property. We’ve got examples for gold, aluminum, and iron already. Now we need silver as the outlier. Maybe “Which substance(s) have the Hunt brothers tried to corner the market on?” 😃 As to conductivity specifically … I checked here [Electrical resistivities of the elements (data page) - Wikipedia](https://en.wikipedia.org/wiki/Electrical_resistivities_of_the_elements_(data_page)) for resistivities (1/conductivity). At 20C we get these values in nano-ohm_meters:[ul][_]Silver: 15.87[_]Gold: 22.14[_]Aluminum: 26.5[\*]Iron: 96.1[/ul]Given those values I’d say that shows iron is the odd man out and the others are fairly tightly clustered. Although they’re far from indistinguishable, so IMO I would not choose conductivity as a good example of a 3 vs 1 property. Unlike color or ferromagnetism. YMMV. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 6, 2017, 8:55pm UTC](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973/40 "2017-11-06T20:55:02Z")
> [@](#): > > Quoth **nate** : > > I have a different take on the answer. I think the answer is 1200. It is based on the combination of the question and answer choices. Like most of these type questions, it doesn’t require you to be clever with math but clever with patterns. > > John likes a number but does not like the result if the first digit is decremented by 1. > > So looking at the possible solutions, you can eliminate all but 1200. He wouldn’t like 900 because 1000 is also a choice, wouldn’t like 1000 because 1100 is also a choice, and wouldn’t like 1100 because 1200 is also a choice. Therefore, only 1200 could be the answer. That doesn’t work, because the answer choices are not part of the question. Under your criterion, would John like 1,000,000? There’s no way to say, which means that you don’t actually have a criterion. This question is unambiguous, because while you can come up with properties that match any answer choice you choose, being a perfect square is by far the most interesting of those properties. The metals one, though, is a terrible question, because there are equally-sound arguments for multiple answers. Gold is an outlier in its color, iron is an outlier in its conductivity and magnetism, and aluminum is an outlier in its chemical properties and melting point. Their densities vary significantly, too, and either gold or aluminum can be considered the biggest outlier there, depending on whether you consider it linearly or geometrically. [Previous page](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973.md?page=1) [Next page](https://boards.straightdope.com/t/can-someone-answer-this-iq-question-for-me/126973.md?page=3)