<p>The diagram shows the uniform cross-section of a solid paper weight $ABCDE$, which is in the shape of a trapezium with a semi-circular hole $ABC$ cut out of it. It is given that&nbsp;$AC$ is parallel to $DE$, $AC=7$ cm, $CD=15$ cm, $DE=21$ cm, $AE=13$ cm, and the height of the trapezium is $12$ cm.</p>
<div class="content-block"><figure class="question-figure aligncenter" style="text-align: center;"><img src="https://vocwkpgapvksartxhhor.supabase.co/storage/v1/object/public/question-images/pasted/1764403676855-2wo3c92nwrw.png" style="max-width: min(350px, 100%); height: auto; display: block;" class="aligncenter custom-width" /></figure></div>
<ol class="abc-list"><li><div class="list-item-paragraph">Find the area of $ABCDE$.</div></li><li><div class="list-item-paragraph">The length of the prism is $30$ cm.  Calculate its</div><ol class="i-list"><li><div class="list-item-paragraph">volume.</div></li><li><div class="list-item-paragraph">surface area.</div></li></ol></li><li><div class="list-item-paragraph">The prism is melted down and recast into a cylinder of radius $8$ cm. Find the height of 	the cylinder.</div></li></ol>

The diagram shows the uniform cross-section of a solid paper weight $ABCDE$, which is in the shape of a trapezium with a semi-circular hole $ABC$ cut out of it. It is given that $AC$ is parallel to $DE$, $AC=7$ cm, $CD=15$ cm, $DE=21$ cm, $AE=13$ cm, and the height of the trapezium is $12$ cm.

The length of the prism is $30$ cm.  Calculate its

The prism is melted down and recast into a cylinder of radius $8$ cm. Find the height of 	the cylinder.

Composite Cross-Section: Trapezium with Semi-Circular Cut-Out

Composite Cross-Section: Trapezium with Semi-Circular Cut-Out

Video Solution: