{"id":216,"date":"2022-04-12T09:54:55","date_gmt":"2022-04-12T09:54:55","guid":{"rendered":"http:\/\/7thclass.deltapublications.in\/?page_id=216"},"modified":"2025-12-19T05:36:26","modified_gmt":"2025-12-19T05:36:26","slug":"j-13-rate-of-change","status":"publish","type":"page","link":"https:\/\/7thclass.deltapublications.in\/index.php\/j-13-rate-of-change\/","title":{"rendered":"J.13 Rate of change"},"content":{"rendered":"\n

Rate of change<\/strong><\/h2>\n\n\n\n

Key notes:<\/p>\n\n\n\n

\ud83d\udd39 What is Rate of Change?<\/strong><\/p>\n\n\n\n

\ud83d\udc49 The rate of change<\/strong> tells us how much one quantity changes compared to another<\/strong>.
\ud83d\udc49 It shows how fast<\/strong> something is increasing or decreasing \u23f1\ufe0f<\/p>\n\n\n\n

\n\n\n\n

\ud83d\udd39 Simple Meaning<\/strong><\/p>\n\n\n\n

\ud83d\udcca Rate of Change = Change in one value \u00f7 Change in another value<\/strong><\/p>\n\n\n\n

\ud83e\uddee Example:<\/p>\n\n\n\n

If a car travels 100 km in 2 hours<\/strong> \ud83d\ude97
\u27a1\ufe0f Rate of change = 100 \u00f7 2 = 50 km per hour<\/strong><\/p>\n\n\n\n

\n\n\n\n

\ud83d\udd39 Where Do We See Rate of Change?<\/strong> \ud83d\udc40<\/p>\n\n\n\n

\u2705 Speed (distance per time) \ud83d\udeb4
\u2705 Money earned per day \ud83d\udcb0
\u2705 Growth of plants per week \ud83c\udf31
\u2705 Temperature change per hour \ud83c\udf21\ufe0f<\/p>\n\n\n\n

\n\n\n\n

\ud83d\udd39 Positive & Negative Rate of Change<\/strong><\/p>\n\n\n\n

\u2795 Positive<\/strong> \u279c value increases \ud83d\udcc8
\u2796 Negative<\/strong> \u279c value decreases \ud83d\udcc9<\/p>\n\n\n\n

\ud83e\uddee Example:<\/p>\n\n\n\n

\ud83d\udcc8 Saving money every day = Positive
\ud83d\udcc9 Losing money every day = Negative<\/p>\n\n\n\n

\n\n\n\n

\ud83d\udd39 Rate of Change in Tables<\/strong> \ud83d\udccb<\/p>\n\n\n\n

\ud83d\udc49 Find how much the values go up or down each step
\ud83d\udc49 Divide the change in output by the change in input<\/p>\n\n\n\n

\n\n\n\n

\ud83d\udd39 Rate of Change in Graphs<\/strong> \ud83d\udcc9\ud83d\udcca<\/p>\n\n\n\n

\ud83d\udc49 Shown by the steepness of the line<\/strong>
\ud83d\udd3a Steep line = Faster change
\ud83d\udd3b Flat line = No change<\/p>\n\n\n\n

\n\n\n\n

\ud83d\udd39 Units Matter!<\/strong> \u26a0\ufe0f<\/p>\n\n\n\n

\ud83d\udccf Always write units (km\/h, \u20b9\/day, \u00b0C\/hour)
\u27a1\ufe0f Units help us understand the rate clearly<\/p>\n\n\n\n

\n\n\n\n

\ud83d\udd39 Real-Life Example<\/strong> \ud83c\udf0d<\/p>\n\n\n\n

\ud83d\ude8c A bus fare increases \u20b95 every year
\u27a1\ufe0f Rate of change = \u20b95 per year<\/strong><\/p>\n\n\n\n

\n\n\n\n

\u2728 Quick Tip<\/strong><\/p>\n\n\n\n

\ud83e\udde0 Rate of change helps us compare how things grow, move, or change over time!<\/em><\/p>\n\n\n\n

\n

Learn with an example<\/strong><\/p>\n\n\n\n

\n
\n

\u2712\ufe0f A dog show enthusiast recorded the weight of the winning dog at recent dog shows.<\/p>\n\n\n

\n
\"\"<\/figure><\/div>\n\n\n

According to the graph, what was the rate of change between 2021 and 2022?<\/strong><\/p>\n\n\n\n

_______ kilograms per year<\/p>\n<\/div><\/div>\n\n\n\n

Plug the numbers into the formula for rate of change and simplify.<\/p>\n\n\n\n

Rate of change = change in value \/ change in time<\/p>\n\n\n\n

= 30 kilograms \u2013 18 kilograms \/ 2022 – 2021<\/p>\n\n\n\n

= 30 kilograms \u2013 18 kilograms \/ 1 year<\/p>\n\n\n\n

= 12 kilograms \/ 1 year <\/p>\n\n\n\n

= 12 kilograms per year<\/p>\n\n\n\n

The rate of change between 2021 and 2022 was 12 kilograms per year.<\/p>\n<\/div><\/div>\n\n\n\n

\n
\n

\u2712\ufe0f A restaurant’s average food preparation time was tracked from day to day as part of an efficiency improvement programme.<\/p>\n\n\n

\n
\"\"<\/figure><\/div>\n\n\n

According to the table, what was the rate of change between Thursday and Friday?<\/strong><\/p>\n\n\n\n

_____ minutes per day<\/p>\n<\/div><\/div>\n\n\n\n

Plug the numbers into the formula for rate of change and simplify.<\/p>\n\n\n\n

Rate of change = change in value \/ change in time<\/p>\n\n\n\n

= 34 minutes \u2013 28 minutes \/ 1 day<\/p>\n\n\n\n

= 6 minutes \/ 1 day<\/p>\n\n\n\n

= 6 minutes per day<\/p>\n\n\n\n

The rate of change between Thursday and Friday was 6minutes per day.<\/p>\n<\/div><\/div>\n\n\n\n

\n
\n

\u2712\ufe0f A restaurant’s average food preparation time was tracked from day to day as part of an efficiency improvement programme.<\/p>\n\n\n\n

\n
\"\"<\/figure><\/div>\n\n\n

According to the graph, what was the rate of change between Monday and Tuesday?<\/strong><\/p>\n<\/div><\/div>\n\n\n\n

_____ minutes per day<\/p>\n<\/div><\/div>\n\n\n\n

Plug the numbers into the formula for rate of change and simplify.<\/p>\n\n\n\n

Rate of change = change in value \/ change in time<\/p>\n\n\n\n

= 34 minutes \u2013 38 minutes \/ 1 day<\/p>\n\n\n\n

= -4 minutes<\/p>\n\n\n\n

= -4 minutes per day<\/p>\n\n\n\n

The rate of change between Monday and Tuesday was<\/p>\n<\/div><\/div>\n\n\n\n

let’s practice! \ud83d\udd8a\ufe0f<\/p>\n<\/div><\/div>\n\n\n\n

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\"\"<\/a><\/figure>\n<\/div>\n\n\n\n
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\"\"<\/a><\/figure>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

Rate of change Key notes: \ud83d\udd39 What is Rate of Change? \ud83d\udc49 The rate of change tells us how much one quantity changes compared to another.\ud83d\udc49 It shows how fast something is increasing or decreasing \u23f1\ufe0f \ud83d\udd39 Simple Meaning \ud83d\udcca Rate of Change = Change in one value \u00f7 Change in another value \ud83e\uddee Example:Continue reading “J.13 Rate of change”<\/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-216","page","type-page","status-publish","hentry","entry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/216","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=216"}],"version-history":[{"count":12,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/216\/revisions"}],"predecessor-version":[{"id":17667,"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/216\/revisions\/17667"}],"wp:attachment":[{"href":"https:\/\/7thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/media?parent=216"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}