Knockout!

Effect

The performer chooses a prominent member of the audience and hands him a piece of chalk and a slate and stands him at one side of the stage, or across the room. The performer stands at the opposite side of the stage and also holds a slate and a piece of chalk. Four more volunteers are asked to stand at their seats in the audience.

The first volunteer is asked to concentrate upon his year of birth. The second thinks of the year in which his wife was born. The third person mentally selects any important year, in the last 20, during which an event of consequence has happened for him. To further vary the numbers selected, the fourth assistant thinks of the first four figures of his telephone number, license number, Social Security Card, etc. After a bit of concentration, the performer writes upon his slate the total of these four mentally chosen numbers.

The four audience standees are now asked to call out their selected numbers, and the assistant on the stage writes them down in a column on the slate he holds. He is requested to add them and call aloud the total, and then show it to the audience. (You can invite members of the audience to take down the numbers and add them for a double check - and this is a very strong point.) The climax arrives when the performer shows his slate to contain the correct total of the four numbers!