A dice program should roll 1 to 6. Which range keeps every roll legal?

• 0 to 9
• 1 to 6
• 1 to 100

What is a random value in a program?

• A value the computer picks fresh on each run
• A value typed by the player
• A value the programmer writes into the code once

Two runs of a dice program must show the same number.

Circle one:   True   False

A game drops a star at a random x from 0 to 400, both ends included. The screen is 400 pixels wide, so it shows x from 0 to 399. Now and then a star never appears. What is the likely cause?

• 400 is in the range but off the screen
• Starting the range at 0 hides the star
• Random picks sometimes return nothing

You run a coin-flip program ten times and see heads every time. What should you conclude?

• The program is proven fair
• Short runs can look lopsided by chance
• The program is broken and can only pick heads

You run the same program three times. What should you write down?

• What stayed the same and what changed
• Only the output of the run that looked right
• Nothing, memory is enough

A Treat-or-Trick program shows Trick below 5 and Treat at 5 or above, from 0 to 10. After a thousand runs each word appears about half the time. What does that tell you?

• The program is broken
• The words are misspelled
• The split sits near the middle of the range

A friend says one winning run proves a dice game is correct. What is wrong with that proof?

• Winning runs do not count
• One run cannot show the broken values chance never picked
• Dice games cannot be tested