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Proportion Calculations (PROP)
Use the key to enter the PROP mode when you want to solve 
a ratio expression.
In PROP mode, you can solve the value of X in the ratio 
expression.
Inputting and Editing Coefficients
• The PROP mode 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.
• Use the coefficient editor screen to input the coefficients of 
a ratio expression. The coefficient editor screen shows 
input cells for each of the coefficients required by the 
currently selected ratio expression type.
• Rules for inputting and editing coefficients
-  Data you input is inserted into the cell where the cursor 
is located. When you register input into a cell, the 
cursor moves to the next cell to the right. 
-  The values and expressions you can input on the 
coefficient editor screen are the same as those you can 
input in the COMP mode with linear format.
-  Press 
 while inputting data clears your current input.
-  After inputting data, press 
. This registers the value 
and displays up to six of its digits in the currently 
selected cell.
-  To change the contents of a cell, use the cursor keys to 
move the cursor to the cell and then input the new data.
• You can clear all coefficients to zero by pressing the  
key while inputting values on the coefficient editor screen. 
a/b = x/d  a/b = c/x 
Key in Display Display
or