Some Circle type thing (Finding the Area)

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Zombot

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Please pardon my crude representation, but this is from the book and there are zero examples of this shape to solve for Area.

I am terrible at math and I have been stuck on this problem for hours...I literally have no where to begin.

I am supposed to find the Area...and I dont really care so much for the answer, but I just wanna learn how to solve these types of problems.

Let me know if you need more information...

Thank you in advanced
 


Your phrase "circle type thing" is not good enough. I hope that the exercise does not refer to the surface area of a capsule shape because the following information is for a two-dimensional object.

Your drawing looks like a rectangle with half a circle stuck on each end.

The area of such a shape is found by adding two easily-calculated areas together:

Circle Area + Rectangle Area

If this does not make sense, then try to imagine the two half circles removed and joined together to make a full circle; what remains is the rectangular part. Shifting the pieces around in our mind like this does not change their combined area. In other words, the area of the circle and rectangle combined is exactly the same as the area of the rectangle with a half circle stuck at each end.

Here is the formula for the area of a rectangle: Length times width (L*W)

Here is the formula for the area of a circle: Pi times radius times radius (Pi*r^2)

Remember, the radius is 1/2 the diameter shown in your drawing.

Can you try it now? 8-)

If you still have questions, please be specific.

 
Sorry for the bad description, but the book did not give us this shape so i had no idea.. my apologies

And with your help I solved it o.o

I combined both halves of the bottom and top half circles to one and took the diameter and divided by it 2 to get 1.5radius

I then did Pi1.5^2 + 7.5 which came out to be 14.6cm squared rounded to the tenth.

I cannot thank you enough. Thank you very much

I guess as a last question is if I have a similar question on a test how do i know when to Circle Area + Rectangle Area or other various combinations X + X
 
I guess as a last question is if I have a similar question on a test how do i know when to Circle Area + Rectangle Area or other various combinations X + X

When you are asked to find the area of some shape that you do not have a formula for, try breaking it up into shapes that you do have formulas for. It is called decomposing the area. In this case, you could decompose into 1 rectangle and 2 semi-circles. 1 semi-circle has half the area of a circle with the same diameter.

Shapes defined exclusively by straight lines can always be decomposed into triangles. So you should be OK with any thing that involves straight lines and fractions of a circle.

Does that make any sense?
 
wow okay that makes a lot of sense tyvm =D so much to the both of you.

you guys helped me more than you know :)
 
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