## How to find the value of R ?

on 17 Feb 2013

### Carlos (view profile)

If

```R1 = 0.173*(E^3/2)*A1^1/3
R2 = 0.173*(E^3/2)*A2^1/3
R3 = 0.173*(E^3/2)*A3^1/3
Wi = (Ni*Ai)/M
```
```for R1    Ni = 10  & A1 = 12
for R2    N2 = 8   & A2 = 1
foe R3    N3 = 4   & A3 = 16
M = sum(Ni*Ri)
E = ( 1,2,...,10)
```

Then

```1/R = sum(wi/Ri)
```

Find R

Greg Heath

### Greg Heath (view profile)

on 17 Feb 2013

Please separate equations by putting them on separate lines.

Thanks.

Walter Roberson

### Walter Roberson (view profile)

on 17 Feb 2013

Reformatted, but they are hard to interpret that way too.

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### Carlos (view profile)

on 18 Feb 2013

Is this what you mean?

```>> A=27;
>> E=1:1:10;
>> R = 0.173*(E.^3/2)*A.^1/3
```
```R =
```
`    Columns 1 through 9`
`      0.7785    6.2280   21.0195   49.8240   97.3125  168.1560  267.0255  398.5920  567.5265`
`    Column 10`
`    778.5000`

### Tae Yeong Kim (view profile)

on 17 Feb 2013
Edited by Tae Yeong Kim

### Tae Yeong Kim (view profile)

on 17 Feb 2013

It is very hard to interpret the equations. Could you form the equations neatly?

### Image Analyst (view profile)

on 17 Feb 2013

Isn't it just

```R = 1 ./ sum(wi./Ri)
```

????? Of course that assumes you already know what wi and Ri are, which none of us do.

### Walter Roberson (view profile)

on 17 Feb 2013
```N = [10 8 4]
A = [12 1 16];
R = ??
M = sum(R .* N);
W = (N .* A) ./ M;
Final_R = 1 ./ sum(W .* R);
```

Unfortunately the definition of R(i) is confused as it is based upon E which appears to be 1:10.

### dashty (view profile)

on 18 Feb 2013

Thanks for all I need the value of R in this equation

R = 0.173*(E^3/2)*A^1/3

If the value of A = 27 and

E= (1,2,3,4,5,6,7,8,9,10)

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