Question
<p>&lt;p&gt;The length of sides of a
square is twice the radius of a circle and perimeter of a rectangle is half the perimeter of the square. If the sum of length and breadth of rectangle is 16 cm, then find the area of the circle (in cm&lt;sup&gt;2&lt;/sup&gt;). [Take &amp;pi; = 2]&lt;/p&gt;</p>Solution
<p><p>Let the length of a square be &lsquo;a&rsquo;.</p> <p>And the radius of a circle be &lsquo;r&rsquo;.</p> <p>Now, a = 2r ----- (i)</p> <p>Perimeter of the rectangle = 1/2 &times; 4a = 2a</p> <p>=&gt; 2(l + b) = 2a</p> <p>=&gt; 2 &times; 16 = 2a</p> <p>=&gt; a = 16 cm</p> <p>Putting value of &lsquo;a&rsquo; in (i) we get,</p> <p>Radius = r = 16/2 = 8 cm</p> <p>Area of the circle = &pi;r<sup>2</sup>&nbsp;= 2 &times; 8 &times; 8 = 128 cm<sup>2</sup>.</p></p>
Working alone, B can complete the work in 30 days. C is twice as efficient as B and A takes 3 days more than it takes C to complete the work. Working to...
A man can complete a task in 20 days, a woman can finish it in 30 days, and a boy can do the same task in 60 days. To complete the task in just 3 days, ...
Arjun can finish 60% of a job in 9 days. Bittu needs 9 more days than Arjun to finish the whole job, and Bittu’s efficiency is 25% higher than Charu�...
- ‘P’ takes 25 days to complete a piece of work. ‘Q’ is 25% more efficient than ‘P’. Find the time taken by them to complete 90% of the work toge...
12 children and 18 men complete an artwork in 9 days. Each child takes twice as long as a man to finish the artwork. How many days will it take for 18 m...
A can fabricate a divider in 10 days , while B alone can assemble it in 30 days, If they construct it together and get an installment of Rs 8200, then f...
A can finish a task in 32 days, while B can complete the same task 8 days sooner than A. If they together earn a total of Rs. 1050 for the job, how much...
A and B individually can complete the work in 20 days and 30 days respectively. If the time taken by C alone to complete the work is 1.25 times the time...
'A' and 'B' together can do a piece of work in 12 days while 'B' and 'C' together can do the same work in 16 days. 'A' started the work alone and worke...
A and B can complete a work together in 30 days. If A alone can complete one-third of the work in ‘x’ days and remaining work is completed by B alon...