MHB Find Area Problem in Multiple Choice Question

AI Thread Summary
To find the area of the shaded blue region, subtract the area of the circle from the area of the square. The area of a square with side length 10 is 100 cm², while the area of a circle with a diameter of 10 is approximately 78.54 cm². The calculation results in a blue area of about 21.5 cm². This method effectively clarifies how to approach similar area problems. The final answer of 21.5 cm² is confirmed as correct.
susanto3311
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hi all...

how to easy find to figure it out this problem..

how to find are that shading blue color..

please, see my picture..

thanks in advance...susanto3311
 

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Hi susanto3311! :)

What is the area of a square with side 10?
And a circle with diameter 10?
 
I like Serena said:
Hi susanto3311! :)

What is the area of a square with side 10?
And a circle with diameter 10?

i don't understand what do you answer...
 
susanto3311 said:
i don't understand what do you answer...

The blue area is the area of the square minus the area of the circle.

A square with side $s$ has area $s^2$.
A circle with diameter $d$ has area $\frac 1 4 \pi d^2$.

What would you get if you calculate those?
 
I like Serena said:
The blue area is the area of the square minus the area of the circle.

A square with side $s$ has area $s^2$.
A circle with diameter $d$ has area $\frac 1 4 \pi d^2$.

What would you get if you calculate those?

hi Serena...

Finally, with your formula my calculation the result is 21.5 cm2.
it's true? please, corrected if my answer is wrong...

thanks Serena...
 

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susanto3311 said:
hi Serena...

Finally, with your formula my calculation the result is 21.5 cm2.
it's true? please, corrected if my answer is wrong...

thanks Serena...

Yep. It's true. (Nod)
 
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