Kmaps and logic gates

I’m going through my boolean logic course work and have a couple questions I hope you can answer.

Kmaps- if you have a Kmap with 6 1s blocked together, you have to decide if you are going to group the “upper 4” or “lower 4” . question #4 in the first practice test is a good example. They chose the “upper right” and got their answer. I chose the “middle or lower right” and got a different answer. Is one inherently better or more correct than the other?

Logic gates- on the hand written logic gates on the answer sheet to the 2nd practice test, there are values (1 or 0) written for the inputs (variables) and the final output. How does one determine what these variables should be based solely on the answer determined from the Kmap?

do you have any screenshots for these two issues/examples?

!

I’m not sure what question is being asked in the practice test examples ( if w is TRUE, x is FALSE) type questions, but at least for the logic gate, it’s a representation of the equation/function, where the answer is 0 or false. The component closest to the final answer (0) represents ‘OR’, which means EITHER of the two minterms (w’z) and (x’z’) are correct (remember to not confuse True with Correct, this was something that I kept doing. So True will equal 1 and Correct basically means the math ‘checks out’). The next two components or functions/operations are CORRECT in that they do equal 0, where w=1 (true) x=1 (true) y=1 (true, even though it doesn’t get used) and z=0 (false).

x’z’ is equivalent to 01= 0 and w’z is equivalent to 01=0

I’m not sure if that makes sense the way I worded it, but my degree is in English, so unfortunately I have to have things explained somewhat explicitly, not just seeing it as a math type problem. Also, visuals are super helpful. I actually got a better understanding of this from a website about electrical circuits, then I worked backwards and understood K-maps and Truth tables.

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They chose the “upper right” and got their answer. I chose the “middle or lower right” and got a different answer. Is one inherently better or more correct than the other?

If you haven’t already, check out this video lecture:

App Academy Learning Lectures: Boolean

If it’s still not clear, I’d highly recommend these lectures (they’re what finally helped me understand it):

Karnaugh Maps
Karnaugh Map Examples
Combinational Logic Design Using Karnaugh Maps

on the hand written logic gates on the answer sheet to the 2nd practice test, there are values (1 or 0) written for the inputs (variables) and the final output. How does one determine what these variables should be based solely on the answer determined from the Kmap?

See if this helps. The values you see in the inputs on the logic gate illustration represent a value that exists in the kmap above it— when w = 1, x = 1, y = 1, and z = 0, (or 1110) the output is 0:

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Can I use any combination of available values and draw a logic gate model based on that? Or is there only one correct set of inputs to represent?

given the answer F(x,y,z) = x’z’ +w’z How did you know that y=1?