{"id":227051,"date":"2025-06-05T18:46:37","date_gmt":"2025-06-05T18:46:37","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=227051"},"modified":"2025-06-05T18:46:39","modified_gmt":"2025-06-05T18:46:39","slug":"ezra-counts-the-number-of-passengers-who-are-already-on-the-bus-when-he-gets-on-each-morning","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/05\/ezra-counts-the-number-of-passengers-who-are-already-on-the-bus-when-he-gets-on-each-morning\/","title":{"rendered":"Ezra counts the number of passengers who are already on the bus when he gets on each morning"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Ezra counts the number of passengers who are already on the bus when he gets on each morning. His data for the last 15 days are shown below. What is the interquartile range of the data? 8, 9, 9, 10, 12, 12, 13, 14, 15, 15, 15, 16, 18, 19, 20<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">To find the <strong>interquartile range (IQR)<\/strong> of a data set, follow these steps:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 1: Order the Data<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The data is already in <strong>ascending order<\/strong>:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>8, 9, 9, 10, 12, 12, 13, 14, 15, 15, 15, 16, 18, 19, 20<\/strong><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 2: Identify the Median (Q2)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">There are <strong>15 numbers<\/strong>, so the <strong>median<\/strong> is the <strong>8th number<\/strong>:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Q2 = 14<\/strong><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Step 3: Find the Lower Quartile (Q1)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The <strong>lower half<\/strong> of the data includes the numbers <strong>before<\/strong> the median:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>8, 9, 9, 10, 12, 12, 13<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is 7 numbers. The <strong>median of these<\/strong> is the 4th number:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Q1 = 10<\/strong><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Step 4: Find the Upper Quartile (Q3)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The <strong>upper half<\/strong> includes the numbers <strong>after<\/strong> the median:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>15, 15, 15, 16, 18, 19, 20<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is also 7 numbers. The <strong>median of these<\/strong> is the 4th number:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Q3 = 16<\/strong><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Step 5: Calculate the Interquartile Range (IQR)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">IQR=Q3\u2212Q1=16\u221210=6\\text{IQR} = Q3 &#8211; Q1 = 16 &#8211; 10 = \\boxed{6}<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"> Explanation:<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The <strong>interquartile range (IQR)<\/strong> is a measure of statistical dispersion, or how spread out the middle 50% of a data set is. It is particularly useful because it ignores outliers and extreme values, focusing only on the central portion of the data. To calculate the IQR, we use the <strong>first quartile (Q1)<\/strong> and the <strong>third quartile (Q3)<\/strong>. Q1 marks the 25th percentile, while Q3 marks the 75th percentile.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In Ezra\u2019s case, he recorded the number of passengers on the bus over 15 days. His data is already sorted, making analysis straightforward. Since there are 15 values, the median (or second quartile, Q2) is the 8th number, which is 14. The lower half of the data (first 7 numbers) is used to find Q1, and the upper half (last 7 numbers) is used for Q3. The middle of the lower half is 10, so Q1 = 10. The middle of the upper half is 16, so Q3 = 16.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Subtracting Q1 from Q3 gives the IQR: IQR=Q3\u2212Q1=16\u221210=6\\text{IQR} = Q3 &#8211; Q1 = 16 &#8211; 10 = 6<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This tells us that the middle 50% of Ezra\u2019s observations range over 6 passengers. The IQR is a robust way to understand variability in data because it isn\u2019t affected by unusually high or low values. It helps in identifying how consistently the number of passengers remains near the middle range.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Final Answer: 6\\boxed{6}<\/strong>.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/06\/learnexams-banner9-62.jpeg\" alt=\"\" class=\"wp-image-227052\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Ezra counts the number of passengers who are already on the bus when he gets on each morning. His data for the last 15 days are shown below. What is the interquartile range of the data? 8, 9, 9, 10, 12, 12, 13, 14, 15, 15, 15, 16, 18, 19, 20 The Correct Answer and [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-227051","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/227051","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=227051"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/227051\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=227051"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=227051"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=227051"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}