A candy machine createssmall coco wafers in the form of one discs. The diameter the eachwafer is 16 millimeters. What is the area of every candy? for this reason the candy, they speak it'sthe form of circular discs. And also they tell us that thediameter of every wafer is 16 millimeters. If I draw a lineacross the circle the goes through thecenter, the size of the line every the way acrossthe circle v the facility is 16 millimeters. Therefore let me write that. For this reason the diameter hereis 16 millimeters. And also they want us tofigure the end the area that the surface ar of thiscandy, or essentially, the area the this circle. And so when wethink around area, we know that the areaof a one is same to pi times the radiusof the circle squared. And also you say, well, theygave united state the diameter. What is the radius? Well, you could remember theradius is 1/2 of the diameter. It's the distancefrom the facility of the circle to the outside,to the boundary of the circle. So it would certainly bethis distance appropriate over here, i m sorry is exactly1/2 that the diameter, therefore it would certainly be 8 millimeters. So wherein we view the radius,we might put 8 millimeters. So the area is goingto be same to pi times 8 millimeterssquared, which would certainly be 64 square millimeters. And also typically, this iswritten through pi after the 64. So you can oftensee it as this is equal to 64 pimillimeters squared. Currently this is the answer,64 pi millimeter squared. However sometimes, it's no sosatisfying to simply leave it together pi. You can say, well, I want toget a estimate of what number this is close to. I want a decimalrepresentation of this. And so, we could start touse approximate values of pi. So the most rough approximatevalue that often tends to be used is saying the pi, avery rough approximation, is same to 3.14. So in that case, wecould say the this is going come be same to 64times 3.14 millimeters squared. And also we can get ourcalculator to figure out what this will bein decimal form. So we have actually 64 times3.14, offers us 200.96. For this reason we might say the thearea is roughly equal come 200.96square millimeters. Currently if we want to get amore precise representation the this-- pi actuallyjust keeps going on and on and also onforever-- we might use the calculator'sinternal depiction of pi, in which case,we'll speak 64 times, and then we need to look forthe pi in the calculator. It's up right here inthis yellow, therefore I'll execute this little second function. Acquire the pi there. Every calculator willbe a small different. Yet 64 time pi. And also now we're going touse the calculator's interior approximationof pi, i beg your pardon is going to be an ext precisethan what I had in the critical one. And also you get 201-- solet me put it over right here so I have the right to write that down--so an ext precise is 201. And I'll round to the nearesthundreds, for this reason you obtain 201.06.


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So much more precise is 201.06square millimeters. For this reason this is closer tothe really answer, because a calculator'srepresentation is an ext precise 보다 this veryrough approximation that what pi is.