Friday, June 14, 2013

XAT 2012 : Quant Question 66 : Mensuration Surface Area

Question

A spherical metal of radius 10 cm is molten and made into 1000 smaller spheres of equal sizes. In this process the surface area of the metal is increased by:

A.    1000 times
B.    100 times
C.    10 times
D.    No Change
E.    None of the above

Correct Answer : 10 times. Choice C

Explanatory Answer
Let the radius of the small spheres be ‘r’ cm.
The amount of metal remains the same in both cases.

Hence, volume of the spherical metal of radius 10 cm should be equal to the volume of the 1000 smaller spheres of radius ‘r’ cm put together.





Therefore, r = 1 cm.
Surface area of a spherical metal of radius 10 cm is
 


Surface area of 1000 smaller spheres put together is



Thus the surface area increased by 10 times.

4 comments:

  1. It becomes 10 times. but increased by 9 times ...

    ReplyDelete
  2. $$$ GENUINE LOAN WITH LOW INTEREST RATE APPLY $$$
    Do you need finance to start up your own business or expand your business, Do you need funds to pay off your debt? We give out loan to interested individuals and company's who are seeking loan with good faith. Are you seriously in need of an urgent loan contact us.

    Email: shadiraaliuloancompany1@gmail.com
    Phone No: +919873186890.

    ReplyDelete
  3. Hello Everybody,
    My name is Mrs Sharon Sim. I live in Singapore and i am a happy woman today? and i told my self that any lender that rescue my family from our poor situation, i will refer any person that is looking for loan to him, he gave me happiness to me and my family, i was in need of a loan of S$250,000.00 to start my life all over as i am a single mother with 3 kids I met this honest and GOD fearing man loan lender that help me with a loan of S$250,000.00 SG. Dollar, he is a GOD fearing man, if you are in need of loan and you will pay back the loan please contact him tell him that is Mrs Sharon, that refer you to him. contact Dr Purva Pius,via email:(urgentloan22@gmail.com) Thank you.

    BORROWERS APPLICATION DETAILS


    1. Name Of Applicant in Full:……..
    2. Telephone Numbers:……….
    3. Address and Location:…….
    4. Amount in request………..
    5. Repayment Period:………..
    6. Purpose Of Loan………….
    7. country…………………
    8. phone…………………..
    9. occupation………………
    10.age/sex…………………
    11.Monthly Income…………..
    12.Email……………..

    Regards.
    Managements
    Email Kindly Contact: urgentloan22@gmail.com

    ReplyDelete
  4. MRS.IRENE QUERY FINANCE IS THE BEST PLACE TO GET A LOAN {mrsirenequery@gmail.com}

    God bless you Mum, I will not stop telling the world about your kindness in my life, I am a single mum with kids to look after. My name is Mrs.Rachel Alex, and I am from Center Drive, Miami Beach, FL . A couple of weeks ago My friend visited me and along our discussion she told me about MRS.IRENE QUERY FINANCE, that they can help me out of my financial situation, I never believed cause I have spend so much money on different loan lenders who did nothing other than running away with my money. I have been in a financial mess for the pass 7 months now,She advised I give it a try so I mailed her and explain all about my financial situation to her, she therefore took me through the loan process and gave me a loan of $180,000.00 at a very low interest rate of 3% and today I am a proud business owner and can now take good care of my kids, If you must contact any firm to get any amount of loan you need with a low interest rate of 3% and better repayment schedule, please contact MRS.IRENE QUERY FINANCE via email{mrsirenequery@gmail.com}

    ReplyDelete