{"id":907,"date":"2012-03-19T18:41:42","date_gmt":"2012-03-19T18:41:42","guid":{"rendered":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/?p=907"},"modified":"2012-03-19T18:42:43","modified_gmt":"2012-03-19T18:42:43","slug":"yet-more-problems-with-significant-figures-using-a-calculator-for-scientific-notation-and-precedence","status":"publish","type":"post","link":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/?p=907","title":{"rendered":"Yet more problems with significant figures, using a calculator for scientific notation and precedence"},"content":{"rendered":"<p><a href=\"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/wp-content\/uploads\/2012\/03\/image.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft size-full wp-image-908\" title=\"image\" src=\"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/wp-content\/uploads\/2012\/03\/image.png\" alt=\"\" width=\"293\" height=\"281\" \/><\/a>The question shown was originally planned to assess students&#8217; ability to estimate, but since we can&#8217;t prevent them from using a calculator, I adapted it to test calculator use as well.<\/p>\n<p>43% of\u00a0the analysed 14943 responses were correct, and the errors made were depressingly familiar:<\/p>\n<p>8.1% were numerically correct but expressed to the nearest order of magnitude not to 1 significant figure.<\/p>\n<p>3.1% were numerically correct but expressed to 2 significant figures.<\/p>\n<p>In 2.9% of responses, the square root on the numerator had only been applied to the first number (4 in the example shown)<\/p>\n<p>2.9% had used 10 to the\u00a0plus 6 instead of 10 to the minus 6 in the denominator (which may have been caused by dividing rather than multiplying by 10 to the minus 6).<\/p>\n<p>So it remains the simple things that cause the problems. Sig figs, calculator use, precedence&#8230;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The question shown was originally planned to assess students&#8217; ability to estimate, but since we can&#8217;t prevent them from using a calculator, I adapted it to test calculator use as well. 43% of\u00a0the analysed 14943 responses were correct, and the &hellip; <a href=\"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/?p=907\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[111],"tags":[208,369,165,207],"class_list":["post-907","post","type-post","status-publish","format-standard","hentry","category-mathematical-misunderstandings","tag-calculator-use","tag-mathematical-misunderstandings","tag-precedence","tag-signficant-figures"],"_links":{"self":[{"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=\/wp\/v2\/posts\/907","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=907"}],"version-history":[{"count":3,"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=\/wp\/v2\/posts\/907\/revisions"}],"predecessor-version":[{"id":911,"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=\/wp\/v2\/posts\/907\/revisions\/911"}],"wp:attachment":[{"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=907"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=907"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/SallyJordan\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=907"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}