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Digital Literacy Computer Basics Computer Basics Binary

The question regards binary numbering. 1st question was 00000001 = 1So what is 00000111

If 00000001 = 1, and 00000011 = 3, What is 00000111?

2 Answers

Steven Parker
Steven Parker
229,644 Points

Here's a method to decode binary numbers. Make a column for each digit, and starting from the right, put a "1" and then as you move left put double the value of the column next to it. Remember, right-to-left (:point_left: THIS WAY :point_left:). You'll get something like this, which is a horizontal version of the helper table shown in the quz:

128  64  32  16   8   4   2   1   <-- 8 columns for 8 digits

Then, put your binary number on the next line, spread into the columns. Now below that, multiply each top number by the binary digit and put the result below. It's easy, since binary digits are either 1 or 0, so you either put the number on top again or zero.

Then finally, add up all the numbers on the bottom row and that's your answer. Using 00000111 for an example:

128  64  32  16   8   4   2   1   <-- starting columns
  0   0   0   0   0   1   1   1   <-- multiply by your binary digits
--- --- --- --- --- --- --- ---
  0   0   0   0   0   4   2   1   <-- add these up:  4 + 2 + 1  =  7

Also, since zeros in front don't count you can skip them. So in this case we really only needed 3 columns.

Saved! Makes sense, and thank you.

Steven Parker
Steven Parker
229,644 Points

stephanie fendley — Glad I could help. You can mark a question solved by choosing a "best answer".
And happy learning!