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Press the <Start> button when the program begins. Five Gregs will appear and one of the Gregs will drop down to be weighed. You can weigh Greg by moving the larger and smaller weights to the right or left on the graduated bar. The bottom (larger) weight shows units and the top(smaller) weight shows hundredths of a gram. Move the weights until the bar is level. The red pointer on the right should be on the center mark when you arrive at Greg's weight.

When you arrive at Greg's weight a plunger will gently push him to the right. You will be prompted to type the difference between the remaining gregs and the Greg you weighed. Type the difference into the edit box and press the <Submit> button. If the amount you submitted is correct, another Greg will land onto the scale. Continue until all Gregs are weighed.

After five Gregs are weighed, you will have a chance to weigh more Gregs by pressing the <Start> button or you can press the <rReport> button to report the time it took to weigh five Gregs.

The program will keep track of the total Gregs you have weighed and the time you took to weigh them.

A challenge - See if you can find the differences mentally.