Brain Teasers

A SCARY LOOKING SCIENTIST PUTS FOUR CARDS IN FRONT OF YOU. ONE SHOWS THE NUMBER 3, ONE SHOWS THE NUMBER 8, ONE IS RED AND ONE IS BROWN.

WHICH TWO CARDS SHOULD YOU TURN OVER TO CONFIRM THE STATEMENT THAT ANY CARD WITH AN EVEN NUMBER ON ONE SIDE MUST BE RED ON THE OTHER?

ANS YOU SHOULD TURN OVER 8 AND BROWN TURNING OVER THE 3 AND FINDING RED, AND TURNING OVER THE RED AND FINDING AN ODD NUMBER WOULD BOTH PROVE NOTHING, AS THE ONLY CONDITION IS THAT AN EVEN NUMBER MUST BE RED ON THE OTHER SIDE. SO ONLY FLIPPING AROUND THE 8 AND THE BROWN WOULD PROVE OR DISPROVE IT.

Easy Math Editor

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Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

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Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$