Here\u2019s an elementary school math question for you all: If you said \u201c5 \u00d7 100 = 500\u201d then I\u2019m sorry but you just flunked second grade math in Japan\u2026 if there were only one question all year.\u00a0The reason is an old teaching method that is employed in elementary and middle schools throughout the country. It\u2019s also a method that many, such as a blogger by the name of Uncorrelated, want stopped as it leads to strange logic where six times seven does not always equal 42 and five times 100 might not equal 500.<\/p>\n <\/p>\n It\u2019s almost an annual event around the internet as someone\u2019s young child with hope for a brighter future comes home with red pen all over their \u201ccorrectly done\u201d test or homework.\u00a0Let\u2019s start with a typical example from twitter. This photo was tweeted with the caption: \u201cMy co-worker\u2019s son\u2019s grade two math test was returned but I can\u2019t understand why he got this wrong\u2026\u201d<\/strong><\/p>\n \n The question reads, \u201cThere are six couches. Seven people sit on each couch, so how many people are sitting all together?\u201d As we can see, the child showed his work using the seven times tables (my least favorite of them all) and put the answer as \u201c42 people\u201d even remembering the units.<\/p>\n However,\u00a0the teacher has corrected the child\u2019s mistake of \u201c6 \u00d7 7 = 42\u201d with the much more correct \u201c7 \u00d7 6 = 42\u201d\u00a0<\/strong>explaining that it\u2019s \u201cseven people times six seats\u201d not the other way around!<\/p>\n The following photo has been well circulated around the internet and appears to show a question from a teacher\u2019s guide along with an explanation of the answer.<\/p>\n \n The question and given answer read:<\/p>\n 1) There are x-yen notebooks 8 of which are bought.\u00a0<\/em> Then there is an explanation of this question for the teacher\u2019s reference which says:<\/p>\n When making a formula that expresses a quantity relationship, children often reverse the left and right hand sides. If children are taught this is okay, then the children are being taught wrong, so you want to address this awkwardness properly. In terms of question 1-A; x \u00d7 8 = y or y = x \u00d7 8 is correct.\u00a0If you follow the flow of the text \u201cx-yen notebooks, eight of which are being bought; the formula when the price is y yen\u201d you should say x \u00d7 8 = y. However in the case that x \u00d7 8 becomes 8 \u00d7 x the meaning becomes \u201c8-yen notebooks, x of which are being bought\u201d<\/strong>\u00a0and is not the same as this problem. It is always important to firmly make them aware of the formula\u2019s meaning.<\/em><\/p>\n<\/blockquote>\n Some, including Uncorrelated, question whether this is an authentic teacher\u2019s manual especially due to the final sentence referring to the formula having \u201cmeaning\u201d which the writers seemed to have just invented.\u00a0Uncorrelated argues that this logic flies in the face of commutative properties<\/strong>\u00a0which are taught shortly after in the school system.\u00a0Commutative properties compare the functions of addition and multiplication to achieve the same result such as\u00a0 2 \u00d7 3 = 3 \u00d7 2 = 2 + 1 + 3 = 3 + 2 + 1.<\/p>\n Taking this one step further, Uncorrelated points out that the formula seems based on the wording of the question which itself can be rearranged more than one way. In fact, if we use a more natural English translation of the question: \u201c8 x-yen notebooks are being bought\u201d this would suggest that 8 \u00d7 x = y is the \u201conly\u201d correct answer that matches the question. This would render an \u201cimportant rule\u201d to be completely arbitrary and kind of absurd.<\/p>\n On the other hand,\u00a0there is something to be said for the clarity of a unified format for expressing formulas and values<\/strong>. It\u2019s one thing to have a genius idea but it\u2019s equally important to have others understand it as well. If I went shopping and the clerk told me my pack of chewing gum cost about 0.025 mL of crude oil from Saudi Arabia, I\u2019d be quite annoyed.<\/p>\n However, I would also be quite impressed at the clerk\u2019s creativity, and that\u2019s what children should be encouraged to have at such a young age. Rather than drilling useless dogma with regards to math, they should be allowed to see numbers in their own way with just enough guidance to help them through. That tends to be when greatness happens.<\/p>\n Source: Blogos \u2013\u00a0Uncorrelated<\/a>\u00a0via\u00a0Hachima Kiko<\/a>\u00a0(Japanese)<\/em> Related articles from RocketNews24:<\/strong><\/p>\n![\"Japanese](\"https:\/\/jetwit.com\/wordpress\/wp-content\/uploads\/2013\/11\/Japanese-Elementary-School-teachers-may-tell-you-\u201c5-x-100-500\u201d-is-wrong1.jpg\")
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\nApples are sold for 100 yen each. If you buy 5 what is the total amount?<\/em><\/p>\n![\"Japanese](\"https:\/\/jetwit.com\/wordpress\/wp-content\/uploads\/2013\/11\/Japanese-Elementary-School-teachers-may-tell-you-\u201c5-x-100-500\u201d-is-wrong2.jpg\")
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\nA: If y-yen is the total price, write a formula to express the relation between x and y.<\/em>
\nx \u00d7 8 = y<\/em><\/p>\n<\/blockquote>\n\n
\nImages: Wikipedia \u2013\u00a0Abrahami<\/a>,\u00a0<\/em>Twitpic \u2013\u00a0string spirits<\/a>,\u00a0<\/em>Twitter \u2013\u00a0genkuroki<\/a><\/em><\/p>\n