Inge is competing in a 400 m race. She runs at a constant speed of 4.6 m\/s for the first 150 m, then 4.2 m\/s for 40 seconds. The remainder of the race takes her 38 seconds to complete. What is Inge’s average speed for the entire race to 1 dp?<\/p>\n\n\n\n
The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n To find Inge’s average speed for the entire race, we first need to calculate the total distance she ran and the total time she took to complete the race.<\/p>\n\n\n\n The race is a 400-meter race, so the total distance covered is: Inge runs the first 150 meters at a constant speed of 4.6 m\/s. To find the time taken for this part, we use the formula: Inge runs at a speed of 4.2 m\/s for 40 seconds. The distance covered during this time is: After the first two parts of the race, Inge has run: The remaining 82 meters take 38 seconds to complete.<\/p>\n\n\n\n Now, we can calculate the total time taken for the entire race. The total time is the sum of the times for each part: The average speed is given by the formula: Thus, Inge’s average speed for the entire race is 3.6 m\/s<\/strong> (to 1 decimal place).<\/p>\n","protected":false},"excerpt":{"rendered":" Inge is competing in a 400 m race. She runs at a constant speed of 4.6 m\/s for the first 150 m, then 4.2 m\/s for 40 seconds. The remainder of the race takes her 38 seconds to complete. What is Inge’s average speed for the entire race to 1 dp? The Correct Answer and […]<\/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-164579","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/164579","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=164579"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/164579\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=164579"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=164579"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=164579"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Step 1: Calculate the total distance<\/h3>\n\n\n\n
[
\\text{Total distance} = 400 \\, \\text{m}
]<\/p>\n\n\n\nStep 2: Calculate the time taken for the first part of the race<\/h3>\n\n\n\n
[
\\text{Time} = \\frac{\\text{Distance}}{\\text{Speed}}
]
[
\\text{Time}_1 = \\frac{150 \\, \\text{m}}{4.6 \\, \\text{m\/s}} = 32.61 \\, \\text{seconds}
]<\/p>\n\n\n\nStep 3: Calculate the distance covered in the second part of the race<\/h3>\n\n\n\n
[
\\text{Distance}_2 = \\text{Speed} \\times \\text{Time}
]
[
\\text{Distance}_2 = 4.2 \\, \\text{m\/s} \\times 40 \\, \\text{s} = 168 \\, \\text{m}
]<\/p>\n\n\n\nStep 4: Calculate the remaining distance<\/h3>\n\n\n\n
[
\\text{Distance}_1 + \\text{Distance}_2 = 150 \\, \\text{m} + 168 \\, \\text{m} = 318 \\, \\text{m}
]
The remaining distance to complete the race is:
[
\\text{Remaining distance} = 400 \\, \\text{m} – 318 \\, \\text{m} = 82 \\, \\text{m}
]<\/p>\n\n\n\nStep 5: Calculate the time taken for the final part of the race<\/h3>\n\n\n\n
Step 6: Calculate the total time<\/h3>\n\n\n\n
[
\\text{Total time} = \\text{Time}_1 + \\text{Time}_2 + \\text{Time}_3
]
[
\\text{Total time} = 32.61 \\, \\text{s} + 40 \\, \\text{s} + 38 \\, \\text{s} = 110.61 \\, \\text{seconds}
]<\/p>\n\n\n\nStep 7: Calculate the average speed<\/h3>\n\n\n\n
[
\\text{Average speed} = \\frac{\\text{Total distance}}{\\text{Total time}}
]
[
\\text{Average speed} = \\frac{400 \\, \\text{m}}{110.61 \\, \\text{s}} \\approx 3.6 \\, \\text{m\/s}
]<\/p>\n\n\n\n