In a secret computer code built entirely of light switches that can only be turned on (1) or off (0), what standard decimal number is represented by the four-switch pattern 1011?
11
In binary, 1011 equals (1 × 8) + (0 × 4) + (1 × 2) + (1 × 1) = 8 + 0 + 2 + 1 = 11.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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