Sum of areas of all squares

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Anonymous
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The midpoints of the sides of a 4 centimeter by 4 centimeter square are interconnected to form a smaller square. The midpoints of the sides of the square thus formed are again interconnected to form another smaller square. If the process will be repeated indefinitely, find the sum of the areas of all squares formed including that of the original square.

ReynDuran
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Re: Sum of areas of all squares

if I'm right!!! the sum of the area of all the square will be 96 square centimeter!!! if I'm wrong please check the addition of all squares that is given!!! Smile and please give us the correct answer!!!

Lj (not verified)
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Re: Sum of areas of all squares

My answer is 32 cm2. I will show my solution, but not now. Wink

RTFVerterra
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Re: Sum of areas of all squares

Uunahan na kita Lj, Hehehe

First Square (the given square)
side, x1 = 4 in
Area, A1 = 42 = 16 in2

Second Square
side, x2 = √(22 + 22) = 2 √2 in
Area, A2 = (2 √2)2 = 8 in2

Third Square
side, x3 = √[ (√2)2 + (√2)2 ] = 2 in
Area, A3 = 22 = 4 in2

Fourth Square
side, x4 = √(12 + 12) = √2 in
Area, A4 = (√2)2 = 2 in2

And the process will continue without end.

Sum of all areas:
A = A1 + A2 + A3 + A4 + ...
A = 16 + 8 + 4 + 2 + ...

The areas are in infinite geometric progression with r = 1/2
S = a1 / (1 - r) = 16 / (1 - 1/2) = 32 in2

See the derivation of formulas of finite and infinite gemetric progressions at Mathalino.com.

dj_dalls08
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Re: Sum of areas of all squares

yeah boy, wazzap sir!?

spencerchuy
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Re: Sum of areas of all squares

ALGEBRA IS NICE SUBJECT

migz
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Re: Sum of areas of all squares

spencerchuy wrote:
ALGEBRA IS NICE SUBJECT

wahhahaha..,,

try mo magsagot ng harvard MIT algebra problems.,,

nakakawindang.,

RTFVerterra
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Re: Sum of areas of all squares

migz wrote:
...try mo magsagot ng harvard MIT algebra problems

Hi migz, share mo sa amin ang link sa MIT algebra problems. Ano pala yung windang? Yay! Big smile