Ratio Calculations
The Ratio app lets you determine the value of X in the ratio expression A : B = X : D (or A : B = C : X) when the values of A, B, C and D are known.
General Procedure for Performing a Ratio Calculation
Example 1: To solve 3 : 8 = X : 12 for X
1. Press 
, select the Ratio app icon, and then press 
.
2. On the menu that appears, select [A:B=X:D] or [A:B=C:X].
Here we want to solve 3 : 8 = X : 12 for X, select [A:B=X:D], and then press .
3. On the Coefficient Editor that appears, input coefficient values.
Here we input the following for the coefficients: A = 3, B = 8, D = 12.
- 3
812 
4. After all the values are the way you want, press .
This displays the solution (value of X).
Press 
, 
, or to return to the Coefficient Editor.
Note
A Math ERROR will occur if you perform a calculation while 0 is input for a coefficient.
Performing the steps below resets all Coefficient Editor coefficients to 1.
- While the Coefficient Editor is displayed, press , , , or 
.
- While a solution is displayed, press or .
You can store the currently displayed calculation result to a variable. For example, performing the following operation while the screen in step 4 is displayed above will store the calculation result to variable A: 
– [A=] > [Store]. For details about variables, see "Variables (A, B, C, D, E, F, x, y, z)".
To change the ratio expression type
1. While the Coefficient Editor is displayed, press .
2. On the menu that appears, select the ratio expression type you want.
Calculation Example
Example 2: To calculate X in the ratio 1 : 2 = X : 10
- – [Ratio] > [A:B=X:D]
1210 
