{"id":1349,"date":"2013-06-14T22:37:23","date_gmt":"2013-06-14T22:37:23","guid":{"rendered":"http:\/\/www.astarmathsandphysics.com\/tutor_profiles\/paul_smith\/paul_smiths_blog\/?p=1349"},"modified":"2013-06-14T22:37:23","modified_gmt":"2013-06-14T22:37:23","slug":"just-emailed-casio","status":"publish","type":"post","link":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2013\/06\/just-emailed-casio\/","title":{"rendered":"Just Emailed Casio"},"content":{"rendered":"<p>There are two things that always annoyed me about their calculators, so I just emailed them to see if they would change their design slightly. I said:<\/p>\n<p>I teach maths and your calculators cause confusion because<br \/>\n1. They tell my students that -3 squared is -9<br \/>\n2. They tell my students that 100+10% (when typed in like this) equals 100.1<br \/>\nPlease rectify these two points so that my students find maths just a little bit easier.<\/p>\n<p>Just got this reply<\/p>\n<p>Thank you for your enquiry.<\/p>\n<p>Casio has passed this onto ourselves, as we are the leading authority on calculators used in UK schools.<\/p>\n<p>All current twin-lines scientific calculators operate using the correct and precise priority of mathematical operations when a calculation is evaluated.<\/p>\n<p>Squaring<br \/>\nRaising to the power 2 MUST take priority over the negative indicator (which is equivalent to multiplication by negative 1).<br \/>\nVerbally we often say &#8220;-3&#8221; have a slight pause &#8220;squared&#8221; which implies we are squaring by -3 but every calculator that uses the correct priority of will evaluate -3^2=-9.<br \/>\nBasic single-line scientific calculators operate on the displayed answer, so if -3 is shown then pressing the squaring key would operate on the whole of (-3), giving the result 9.<\/p>\n<p>Percentages<br \/>\nAgain, the calculator is mathematically precise 10%=0.1, so 100 + 10% = 100.1.<br \/>\nSome single-line calculators have a percentage shortcut that does allow you to add a percentage of the displayed amount. Different brands and models can have their own interpretations of a percentage key. In my teaching experience, I always banned my students from using a percentage key for this very reason.<\/p>\n<p>In summary, the current range of Casio scientific calculators are designed to encourage accurate calculations using the correct mathematical syntax and priorities of operations. These are listed in the back of the User Guide for further reference.<\/p>\n<p>Kind regards<\/p>\n<p>Stephen<\/p>\n<p>Stephen Kean<br \/>\nScience Studio<br \/>\n5 Lakeside Business Park<br \/>\nMiddle Aston<br \/>\nBicester<br \/>\nOxon<\/p>\n","protected":false},"excerpt":{"rendered":"<p>There are two things that always annoyed me about their calculators, so I just emailed them to see if they would change their design slightly. I said: I teach maths and your calculators cause confusion because 1. They tell my &hellip; <a href=\"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2013\/06\/just-emailed-casio\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[1],"tags":[],"class_list":["post-1349","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p3Wm4j-lL","jetpack-related-posts":[{"id":1328,"url":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2013\/05\/the-future-for-calculators\/","url_meta":{"origin":1349,"position":0},"title":"The future for calculators","author":"taxicle","date":"May 15, 2013","format":false,"excerpt":"Is app stores, wifi, sd cards. Can't think why someone hasn't made a calculator with all this lovely stuff.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1741,"url":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2013\/12\/do-a-bit-to-save-the-world\/","url_meta":{"origin":1349,"position":1},"title":"Do a Bit to Save the World","author":"taxicle","date":"December 28, 2013","format":false,"excerpt":"Everyone can improve their little corner of the world. My obsession a the moment is finding uses for the things I might throw away. Instead of throwing them away I advertise them on freecycle - I have given away kettle cable, calculators, laptop chargers, and taken and found a use\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1857,"url":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2014\/05\/campaign-for-smiths-law-to-be-part-of-c1-a-level-maths-curriculum\/","url_meta":{"origin":1349,"position":2},"title":"Campaign for Smith&#8217;s Law to be Part of C1 A Level Maths Curriculum","author":"taxicle","date":"May 6, 2014","format":false,"excerpt":"Smith's Law states: The area between two curves is the integral of the top curve minus the bottom curve. I have emailed edexcel asking them to put this on their syllabus. If you think this is a vanity campaign, think of Boltzmann, after whom a constant is named - botzmann's\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":152,"url":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2011\/01\/request-from-tom-cruise\/","url_meta":{"origin":1349,"position":3},"title":"Request from Tom Cruise","author":"taxicle","date":"January 24, 2011","format":false,"excerpt":"Tom Cruise: Can I have arrange a maths tutor? Me: Sorry Tom. We don't tutor short people. Abrupt end to conversation. I thought this worth a blog post. Tom emailed me, maybe having read the above. Hey astarmathsandphysics.com, I didn't request a tutor from you. You're just bitter Tom. I\u2026","rel":"","context":"With 1 comment","block_context":{"text":"With 1 comment","link":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2011\/01\/request-from-tom-cruise\/#comments"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":414,"url":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2011\/11\/the-best-maths-tutor-i-never-met\/","url_meta":{"origin":1349,"position":4},"title":"The Best Maths Tutor I Never Met","author":"taxicle","date":"November 22, 2011","format":false,"excerpt":"Her name is Miriam Linehan and she works in North West London. She phoned me asking about my website, but I am looking for a partner and she is not interested in working with anyone else. Nevertheless, she is frank and honest, has an MSc from Imperial and has registered\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1849,"url":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/2014\/05\/please-make-formulae-consisten-on-gcse-maths-exam-papers\/","url_meta":{"origin":1349,"position":5},"title":"Please make formulae consistent on GCSE maths exam papers","author":"taxicle","date":"May 6, 2014","format":false,"excerpt":"to aqa I sent an email ie please use the formula Area=1\/2ab sin C to mean you can label the triangle in the same way as for the cosine rule a^2 =b^2 +c^2 -2bc con A. I'm sorry I don't have your name but to respond to your query we\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"_links":{"self":[{"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/posts\/1349","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/comments?post=1349"}],"version-history":[{"count":0,"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/posts\/1349\/revisions"}],"wp:attachment":[{"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/media?parent=1349"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/categories?post=1349"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/astarmathsandphysics.com\/blog\/paulsmith\/wp-json\/wp\/v2\/tags?post=1349"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}