A candy machine createssmall coco wafers in the form of one discs. The diameter that eachwafer is 16 millimeters. What is the area of each candy? so the candy, they speak it'sthe form of one discs. And also they tell united state that thediameter of every wafer is 16 millimeters. If I draw a lineacross the circle that goes with thecenter, the length of the line every the way acrossthe circle with the facility is 16 millimeters. Therefore let me write that. So the diameter hereis 16 millimeters. And they want united state tofigure the end the area of the surface of thiscandy, or essentially, the area the this circle. And so as soon as wethink around area, we know that the areaof a one is equal to pi time the radiusof the circle squared. And you say, well, theygave united state the diameter. What is the radius? Well, you can remember theradius is 1/2 that the diameter. It's the distancefrom the facility of the circle come the outside,to the boundary of the circle. So it would bethis distance best over here, which is exactly1/2 the the diameter, therefore it would certainly be 8 millimeters. So whereby we check out the radius,we could put 8 millimeters. So the area is goingto be equal to pi time 8 millimeterssquared, which would be 64 square millimeters. And also typically, this iswritten v pi after ~ the 64. So you might oftensee it as this is equal to 64 pimillimeters squared. Currently this is the answer,64 pi millimeter squared. Yet sometimes, it's not sosatisfying to just leave it together pi. You can say, well, I desire toget a calculation of what number this is nearby to. I desire a decimalrepresentation the this. And so, we can start touse approximate values of pi. Therefore the many rough approximatevalue that often tends to be provided is saying that pi, avery turbulent approximation, is same to 3.14. Therefore in the case, wecould say that this is going come be equal to 64times 3.14 millimeter squared. And also we can gain ourcalculator to number out what this will certainly bein decimal form. For this reason we have 64 times3.14, provides us 200.96. Therefore we might say that thearea is approximately equal to 200.96square millimeters. Now if we desire to gain amore accurate representation of this-- pi actuallyjust keeps walking on and on and also onforever-- we can use the calculator'sinternal representation of pi, in i m sorry case,we'll say 64 times, and then we have to look forthe pi in the calculator. It's up here inthis yellow, for this reason I'll carry out this little 2nd function. Get the pi there. Every calculator willbe a little different. But 64 time pi. And also now we're going touse the calculator's internal approximationof pi, i m sorry is going to be much more precisethan what I had in the critical one. And also you acquire 201-- solet me put it over here so I can write the down--so more precise is 201. And I'll round to the nearesthundreds, so you get 201.06.


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