When the game starts you will see a number line that is three units long. The units are divided into ten equal parts, or tenths of a unit.

Watch carefully after you press the <Start> button because the Blinker Transporter will zoom in and inject Blinker onto a stream on a remote planet. Blinker is unhappy about being deposited into a stream and he wants to be picked up. The Transporter navigator forgot where Blinker was deposited so a Rescue Transporter will need to be navigated to Blinker's location. Help guide the Rescue Transporter to Blinker's location by determining his position to the nearest thousandths of a unit on the number line.

You do this by entering the minimum and maximum amounts that he might be between. If Blinker is between the two amounts you entered, a bar will appear on the number line that shows your entry. If Blinker is not between the two amounts entered you will be told this in the notification window. You may then change the minimum or maximum amounts.

If the difference between the minimum and maximum amounts is equal to or smaller than 1, that portion of the line will be magnified 10 times to a tenths number line. Each tenths unit in the tenths number line is divided into ten parts or hundredths of a unit. You may now guess Blinker's position in tenths or hundredths.

If the difference between the maximum and minimum amounts is equal to or smaller than one-tenth (0.1), that portion of the line will be magnified 10 times to a hundredths number line. Each unit of the hundredths number line is divided into ten parts or thousandths of a unit. You may now guess Blinker's position in hundredths or thousandths of a unit.

Your are trying to get closer to Blinker's position with your guesses. If either of your minimum or maximum guesses is at Blinker's position, the Blinker Rescue Transportation will pick Blinker up.

Your score is the number of times you press the <OK> button and is shown in the Attempts window. Press the <Report> button to make a report card. This button will open a dialog that asks you to submit your name. You may prefer to submit a code for your name. The <Send> key on the dialog box will open a new browser window with your printable report card

There is a lot of strategy in this game. For example, if your minimum and maximum guesses were 2.77 and 2.8 and you were told that Blinker was between these two amounts, a bar would show Blinker's position. If your next minimum and maximum guesses were 2.78 and 2.8 and you were told that Blinker is not between 2.78 and 2.8 it would mean that Blinker would be between 2.77 and 2.78.

This game shows that there exists a fraction between any two fractions, making the set of rational (fractional) numbers a dense set. Compare this to the set of whole numbers. There is no whole number, for example, between 2 and 3.

You should try to find Blinker in less than 20 attempts.