Interactivate: Random Number Generators

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Call Stack
#	Time	Memory	Function	Location
1	0.0004	96768	{main}( )	../discussion.php5:0
2	0.0010	177376	include_once( '/var/www/html/interactivate/config/standardIncludes.php5' )	../discussion.php5:22
3	2.5617	18516784	SWAT->startSession( )	../standardIncludes.php5:110
4	2.5618	18516784	session_start ( )	../SWAT.php5:108

( ! ) Notice: session_start() [function.session-start]: Server 127.0.0.1 (tcp 21201) failed with: Failed reading line from stream (0) in /var/www/html/common-2.3/SWAT/SWAT.php5 on line 108

Call Stack

Time

Memory

Function

Location

0.0004

96768

{main}( )

../discussion.php5:0

0.0010

177376

include_once( '/var/www/html/interactivate/config/standardIncludes.php5' )

../discussion.php5:22

2.5617

18516784

SWAT->startSession( )

../standardIncludes.php5:110

2.5618

18516784

session_start ( )

../SWAT.php5:108

Mentor: Can you come up with several fair ways to randomly choose a number from 1 to 3? From 1 to 5? From 1 to N? (That means your method should work for any number.)

Student 1: We can put as many numbered balls in a bag as we want, and pull one out each time we need a random number:

Student 2: Or we can buy a lottery machine:

Student 3: Or we can build a spinner:

Mentor: Indeed, all these methods will work for any number. We can also use a computer program to give us numbers in a fair way. These programs, not surprisingly, are called random number generators.

Can you come up with more ways to randomly choose a number?