Introduction: Magic Grid Trick
Effect: Without looking, you tell a volunteer to circle any number in a grid from 1-25 and cross out every other number in its row and column. Then you say to do it four more times without using a crossed-out or circled number. Next, you tell them to add the five circled numbers together and keep the total secret. Finally, you reveal the total without looking at what numbers your volunteer picked.
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Step 1: Setup
Draw a grid like I just showed you, and write the number 65 on some paper and put it in your pocket.
Step 2: How It Works
Some math thing says that if you do that, it will always equal 65. To perform, draw or print a grid and hide a piece of paper with "65" somewhere. Then just say somthing like what I said in the intro.
Magic Grid Trick Done!