Section 6: Functions 83
Now using the display execution form, PI, find the area of Europa, a moon of Jupiter with a diameter of 1950 miles.
Keystrokes Display
1950
 1950 _

g X2
 3,802,500.000

XEQ
 XEQ _ _

ALPHA PI ALPHA
 3.1416
The quantity pi.
×
 11,945,906.07
Area of Europa in square miles.
Percentages
The  %  (percent) function is a two-number function that allows you to compute percentages. To find the percentage of a number:
 1. Key in the base number. 2. Press ENTER  . 3. Key in the number representing the percent rate. 3. Press g  %  .
Example: About 94% of the weight of a tomato is water. If a particular tomato weighs 500 gram, what amount of the weight of the tomato is water?
Keystrokes Display
500
 500 _
The base number.
ENTER
 500

94
 94 _
The percent of water.
g  %
 470
The weight in grams of water in a 500-gram tomato.
When you executed  %  , the stack contents were changed...
...from this...           ...to this.

 T 0

 T 0

 Z 0

 Z 0

 Y 500
Base.     %
 Y 500
Base.

 X 94
Rate.
 X 470