Edit Description

Fill up the form and submit

Question

Two small circular parks of diameter 16 meter and 12 meter are to be replaced by a bigger circular park. What would be the radius of this new park, if the new park has to occupy the same space as the two small parks?

20 meter

15 meter

10 meter

100 meter

ANSWER : 3

Descrption

&nbsp;We know,Area of circle, A = πr²&nbsp;&nbsp;diameter of first circle &nbsp;= 16m &nbsp;&nbsp;∴ radius = &nbsp;&lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mn&gt;16&lt;/mn&gt;&lt;mo&gt;&nbsp;&lt;/mo&gt;&lt;/mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mfrac&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/math&gt; = 8m&nbsp;&nbsp;∴ &nbsp;Area of first circle, A₁ = π x 8²= π x 64 = 201m²&nbsp;diameter of second circle &nbsp; &nbsp;= 12m &nbsp;&nbsp;∴ &nbsp;radius = &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mn&gt;12&lt;/mn&gt;&lt;mo&gt;&nbsp;&lt;/mo&gt;&lt;/mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mfrac&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/math&gt; = 6m&nbsp;&nbsp;Area of second circle, A₂ = π x 6²= π x 36 = 113m²Sum of two circle,&nbsp;201m² + 113m² = 314m²According to question, Large Circle:314= πr²r² = &lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mn&gt;314&lt;/mn&gt;&lt;mo&gt;&nbsp;&lt;/mo&gt;&lt;/mrow&gt;&lt;mi&gt;π&lt;/mi&gt;&lt;/mfrac&gt;&lt;/math&gt;r² =&lt;math xmlns="http://www.w3.org/1998/Math/MathML"&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mn&gt;314&lt;/mn&gt;&lt;mo&gt;&nbsp;&lt;/mo&gt;&lt;/mrow&gt;&lt;mn&gt;3.14&lt;/mn&gt;&lt;/mfrac&gt;&lt;/math&gt; &nbsp; [∵ π = 3.14]r² = 100r = √100r = 10m

Please, login first. click here to login

Cancel Login

Edit Description

Question

Download Our Mobile Apps

Satt policy

Main Features

Subscribe our newsletter