Excel formula I have a round disc 1800mm in diameter I want to calculate in excel the surface area of 1800mm in m2 and i have 38 discs. what is the total surface area inn square metres is it 1800*3.14=5652 5.65square metres ?

hi Phyllis.
this link will tell you how.
How to Calculate the Volume of Sphere
if you need more help go to this link.
How do you measure ball shape Google Search

You can view this question as what is the surface area of the 13 inch round pan, and then with it being 2 inches deep, calculate the volume.

Surface area = pi * r ^ 2, where r is the radius of the pan
In this case, the diameter is 13 inches, so the radius will be 6.5 inches.

Putting it into the formula, we get surface area = pi * 6.5 ^ 2.

Because of BEDMAS, we have to do the square before we multiply.

Surface area = pi * (6.5 ^ 2)
= 132.7square inches.

To get the volume, we multiply this surface area by the depth of 2 inches.

Volume = surface area * height
Volume = 132.7 * 2
Volume = 265.4 cubic inches.

Good luck,

Paul

To get around this, you can calculate your numbers as percentages first. For example, if you type the formula =10/100 in cell A2, Excel will display the result as 0.1. If you then format that decimal as a percentage, the number will be displayed as 10%, as you 'd expect.Aug 2, 2011


How to do percentages in Excel - Office Blogs

https://blogs.office.com/2011/08/02/how-to-do-percentages-in-excel/
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How to Calculate Percentages in Excel

www.excelfunctions.net > Excel-Formulas
Two Percentage Calculation Types. Calculate a Percentage as a Proportion.Calculate Percentage Change. Displaying Percentages in Excel Cells ...

Excel formula: Get percentage of total ' Exceljet

https://exceljet.net/formula/get-percentage-of-total
Excel simply divides the values in column C by the total in C11. For the formula shown, the result is the decimal number .63. Because the Percentage number format is applied to cell E6, Excel displays .63 as 63%.

area formula is PI x r squared
that is 3.1417 times the radius of the circle squared
example is:- 3.1417 times 3 inches squared =3.1417 times 3x3=3.1417x9=28.279 square inches if you want to work back from a circumference measurement, the formula for circumference is 2 x PI x radius or PI x diameter
if you have a circumference of 12 inches then the dia is calculated 12 inches = dia x PI to get the diameter , divide the 12 inches by PI and that will be the diameter so that is 12 divided by 3.1417 =3.819 inches
now you can go from the first formula the radius is the diameter divided by 2 so the radius will be 3.819 divided by 2 = 1.909 inches
so applying the area formula it becomes 3.1417 times 1.909 times 1.909 =11.458 square inches
to find your answer simply substitute the dimensions in place of the example figures.in the relevant formula.

Circumference of a Circle: 2 x pi x radius - OR - pi x diameter,

or if you need some sphere calculations?

Sphere Surface Area: 4 X pi X radius squared OR
pi X diameter squared Sphere Volume: 4/3 X pi X radius cubed OR
( pi X diameter cubed ) / 6
By the way.......... "pi" = 3.1415926536

I will not try to guess what that diameter represents, so I will give you all mensuration formulas for the area of a regular polygon.
s is the measure of the side, r the radius of the inscribed circle, R the radius of the circumscribed circle, and n the number of sides.
If the angle unit in your calculator is the degree, use 180 instead of Pi. Use the formulas with PI if angle unit is set to radians.
In the formulas on the last line of the display screen (the formulas with sine functions) the radius r should be R (circumscribed circle radius). cot is the reciprocal of the tangent function (cot(x)=1/tan(x) )

You sort out the formula for the surface you have to calculate then substitute the numerical values for the variables (sides, bases, heights), the constants if any (pi, etc.) an press = to get the result
Ex Square with side= 2m
Surface area=side^2
Area : 2 [X^2][=] result is 4 m^2
Circle of radius r=3 cm
Area: Pi* 3[^2]=28.27 cm^2

Hello,
This calculator does not have a program to which you give the equation, and which returns the solutions. Sorry. You have to use the formulas you learned.
Let the equation be ax^2 +bx+c=0
You compute the discriminant Callit disc.
disc= (b^2-4*a*c)
1. If discriminant is larger than zero you have two solutions. Let us call them x1 and x2.
Then x1=(-b+square root of disc)/(2*a)
and x2= (-b-square root of disc)/(2*a)

2. If disc=0 , square root of disc =0 and x1=x2=-b/(2*a)
3. If disc is negative, there are no real solutions.

To find the solutions you replace a, b, and c by their numerical values, to calculate disc, its square root, and calculate X1 and X2.

Hope it helps.

Hello,
This calculator does not have a program to which you give the equation, and which returns the solutions. Sorry. You have to use the formulas you learned.
Let the equation be ax^2 +bx+c=0
You compute the discriminant Call it disc.
disc= (b^2-4*a*c)
1. If discriminant is larger than zero you have two solutions. Let us call them x1 and x2.
Then x1=(-b+square root of disc)/(2*a)
and x2= (-b-square root of disc)/(2*a)

2. If disc=0 , square root of disc =0 and x1=x2=-b/(2*a)
3. If disc is negative, there are no real solutions.

To find the solutions you replace a, b, and c by their numerical values, to calculate disc, its square root, and calculate X1 and X2.

Hope it helps.