{"id":451,"date":"2022-04-12T10:37:25","date_gmt":"2022-04-12T10:37:25","guid":{"rendered":"http:\/\/7thclass.deltapublications.in\/?page_id=451"},"modified":"2025-11-10T07:08:48","modified_gmt":"2025-11-10T07:08:48","slug":"w-6-circles-word-problems","status":"publish","type":"page","link":"https:\/\/7thclass.deltapublications.in\/index.php\/w-6-circles-word-problems\/","title":{"rendered":"W.6 Circles: word problems"},"content":{"rendered":"\n<h2 class=\"wp-block-heading has-text-align-center has-text-color\" style=\"color:#00056d;text-transform:uppercase\"><strong> Circles: word problems<\/strong><\/h2>\n\n\n\n<p class=\"has-text-color has-huge-font-size\" style=\"color:#74008b\">key notes :<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-text-color has-link-color has-fixed-layout\" style=\"color:#000060\"><tbody><tr><td><strong>Key Formulas to Remember<\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p><strong>Radius and Diameter:  <\/strong><\/p>\n\n\n\n<p>                        d=2r,r=d\/2<\/p>\n\n\n\n<p><strong>Circumference (Perimeter of Circle): <\/strong><\/p>\n\n\n\n<p>                        C=2\u03c0r or C=\u03c0d<\/p>\n\n\n\n<p><strong>Area of Circle: <\/strong><\/p>\n\n\n\n<p>                        A=\u03c0r2<\/p>\n\n\n\n<p>\ud83d\udc49 Use \u03c0=3.14 or 22\/7.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-text-color has-link-color has-fixed-layout\" style=\"color:#000060\"><tbody><tr><td><strong>Steps to Solve Word Problems<\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Read the problem carefully.<\/strong><\/li>\n\n\n\n<li>Identify whether you need <strong>radius, diameter, area, or circumference<\/strong>.<\/li>\n\n\n\n<li><strong>Write the formula<\/strong> clearly.<\/li>\n\n\n\n<li><strong>Substitute the given values<\/strong> into the formula.<\/li>\n\n\n\n<li><strong>Solve step by step<\/strong> and write the final answer with correct units.<\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-text-color has-link-color has-fixed-layout\" style=\"color:#000060\"><tbody><tr><td><strong><strong>Solved Word Problems<\/strong><\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h3 class=\"wp-block-heading has-normal-font-size\"><strong>Example 1:<\/strong> Finding circumference<\/h3>\n\n\n\n<p>A circular garden has a radius of 7 m. Find its circumference.<\/p>\n\n\n\n<p>C=2\u03c0r=2\u00d722\/7\u00d77=44\u2009m<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-normal-font-size\"><strong>Example 2<\/strong>: Finding area<\/h3>\n\n\n\n<p>A circular park has diameter 14 m. Find its area.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Radius = 14\/2=7\u2009m<\/li>\n<\/ul>\n\n\n\n<p> A=\u03c0r<sup>2<\/sup>=22\/7\u00d77\u00d77=154\u2009m<sup>2<\/sup><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-normal-font-size\"><strong>Example 3:<\/strong> From circumference to diameter<\/h3>\n\n\n\n<p>The circumference of a wheel is 62.8 cm. Find its radius.<\/p>\n\n\n\n<p>C=2\u03c0r\u2005\u200a\u27f9\u2005\u200ar=C\/2\u03c0=62.8\/(2\u00d73.14)=10\u2009cm<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-normal-font-size\"><strong>Example 4: <\/strong>Real-life application<\/h3>\n\n\n\n<p>A wire is bent in the form of a circle with radius 14 cm. Find the length of the wire.<\/p>\n\n\n\n<p>Length&nbsp;of&nbsp;wire=Circumference=2\u03c0r=2\u00d722\/7\u00d714=88\u2009cm<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-normal-font-size\"><strong>Example 5: <\/strong>Find area from diameter<\/h3>\n\n\n\n<p>A circular table has a diameter of 2 m. Find its area.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Radius = 1\u2009m<\/li>\n<\/ul>\n\n\n\n<p>A=\u03c0r<sup>2<\/sup>=3.14\u00d71<sup>2<\/sup>=3.14\u2009m<sup>2<\/sup><\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-text-color has-link-color has-fixed-layout\" style=\"color:#000060\"><tbody><tr><td><strong><strong><strong>Practice Questions<\/strong><\/strong><\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Find the circumference of a circle with diameter 28 cm.<\/li>\n\n\n\n<li>A circular pond has a radius of 21 m. Find its area.<\/li>\n\n\n\n<li>The circumference of a circular track is 440 m. Find its radius (use \u03c0=22\/7\u200b).<\/li>\n\n\n\n<li>A circular park has a diameter of 20 m. Find its area and circumference.<\/li>\n\n\n\n<li>A rope is tied around a circular field of radius 35 m. Find the length of the rope and the area of the field.<\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-text-color has-link-color has-fixed-layout\" style=\"color:#000060\"><tbody><tr><td><strong><strong><strong>\ud83d\udccc <strong>Important Tip:<\/strong><\/strong><\/strong><\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Perimeter (Circumference) \u2192 linear units (cm, m)<\/strong><\/li>\n\n\n\n<li><strong>Area \u2192 square units (cm\u00b2, m\u00b2)<\/strong><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><\/p>\n\n\n\n<p class=\"has-text-align-center has-text-color has-huge-font-size\" style=\"color:#105000\"><strong>Learn with an example<\/strong><\/p>\n\n\n\n<div class=\"wp-block-group has-primary-color has-text-color has-background has-normal-font-size\" style=\"background-color:#aab2f9\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group has-primary-color has-background-background-color has-text-color has-background\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"has-text-color\" style=\"color:#b00012\">\u27a1\ufe0f <strong>The button on Bryce&#8217;s coat has a diameter of 8 millimetres. What is the button&#8217;s circumference?<\/strong><\/p>\n\n\n\n<p>Use 3.14 for&nbsp;\u200b\ud835\udf0b.<\/p>\n\n\n\n<p>&nbsp;______ millimetres<\/p>\n<\/div><\/div>\n\n\n\n<p>The diameter is 8 millimetres. Replace&nbsp;<em>d<\/em>&nbsp;by 8 in the formula.<\/p>\n\n\n\n<p>C = \u200b\ud835\udf0b \u00d7 d<\/p>\n\n\n\n<p>\u2248 3.14 \u00d7 8<\/p>\n\n\n\n<p>\u2248 25.12<\/p>\n\n\n\n<p>The circumference is about 25.12 millimetres.<\/p>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-group has-primary-color has-text-color has-background has-normal-font-size\" style=\"background-color:#dcf1ba\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group has-primary-color has-background-background-color has-text-color has-background\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"has-text-color\" style=\"color:#b00012\">\u27a1\ufe0f <strong>The button on Maddie&#8217;s jacket has a radius of 4 millimetres. What is the button&#8217;s circumference?<\/strong><\/p>\n\n\n\n<p>Use 3.14 for&nbsp;\u200b\ud835\udf0b.<\/p>\n\n\n\n<p>&nbsp;_____ millimetres<\/p>\n<\/div><\/div>\n\n\n\n<p>The radius is 4 millimetres. Replace r by 4 in the formula.<\/p>\n\n\n\n<p>C = 2 \u00d7 \u200b\ud835\udf0b \u00d7 r<\/p>\n\n\n\n<p>\u2248 2 \u00d7 3.14 \u00d7 4<\/p>\n\n\n\n<p>\u2248 25.12<\/p>\n\n\n\n<p>The circumference is about 25.12 millimetres.<\/p>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-group has-primary-color has-text-color has-background has-normal-font-size\" style=\"background-color:#f2abab\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group has-primary-color has-background-background-color has-text-color has-background\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"has-text-color\" style=\"color:#b00012\">\u27a1\ufe0f <strong>After stepping into a room with unusual lighting, Betty&#8217;s pupil has a diameter of 6 millimetres. What is the pupil&#8217;s circumference?<\/strong><\/p>\n\n\n\n<p>Use 3.14 for&nbsp;\u200b\ud835\udf0b.<\/p>\n\n\n\n<p>&nbsp;________ millimetres<\/p>\n<\/div><\/div>\n\n\n\n<p>The diameter is 6 millimetres. Replace d by 6 in the formula.<\/p>\n\n\n\n<p>C = \u200b\ud835\udf0b \u00d7 d<\/p>\n\n\n\n<p>\u2248 3.14 \u00d7 6<\/p>\n\n\n\n<p>\u2248 18.84<\/p>\n\n\n\n<p>The circumference is about 18.84 millimetres.<\/p>\n<\/div><\/div>\n\n\n\n<p class=\"has-text-color has-large-font-size\" style=\"color:#d90000\">Let&#8217;s practice!\ud83d\udd8a\ufe0f<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/wordwall.net\/play\/101655\/204\/416\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-130.png\" alt=\"\" class=\"wp-image-6887\" srcset=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-130.png 500w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-130-300x300.png 300w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-130-150x150.png 150w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-2-130-400x400.png 400w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/a><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/wordwall.net\/play\/101657\/644\/722\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-132.png\" alt=\"\" class=\"wp-image-6888\" srcset=\"https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-132.png 500w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-132-300x300.png 300w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-132-150x150.png 150w, https:\/\/7thclass.deltapublications.in\/wp-content\/uploads\/2023\/05\/Worksheet-1-1-1-132-400x400.png 400w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/a><\/figure>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Circles: word problems key notes : Key Formulas to Remember Radius and Diameter: d=2r,r=d\/2 Circumference (Perimeter of Circle): C=2\u03c0r or C=\u03c0d Area of Circle: A=\u03c0r2 \ud83d\udc49 Use \u03c0=3.14 or 22\/7. Steps to Solve Word Problems Solved Word Problems Example 1: Finding circumference A circular garden has a radius of 7 m. Find its circumference. C=2\u03c0r=2\u00d722\/7\u00d77=44\u2009m<a class=\"more-link\" href=\"https:\/\/7thclass.deltapublications.in\/index.php\/w-6-circles-word-problems\/\">Continue reading <span class=\"screen-reader-text\">&#8220;W.6 Circles: word problems&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"om_disable_all_campaigns":false,"footnotes":""},"class_list":["post-451","page","type-page","status-publish","hentry","entry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/451","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/comments?post=451"}],"version-history":[{"count":19,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/451\/revisions"}],"predecessor-version":[{"id":17561,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/451\/revisions\/17561"}],"wp:attachment":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/media?parent=451"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}