CAIS
posted by Ti .
Build a majority circuit. Three inputs and one output. The vaue of its output is 1 and only if two or more of its inputs are 1, otherwise the output of circuit is 0.

Is the logic this?
If NOT( A and B), NOR A and C, NOR if A and D, Nor if B and C, NoR if B and D, NOR if C and D, then ouput=1 ?
or, you could use a counter circuit, counting inputs sequential (put a time delay for each). 
Well it just is asking me to create a circuit with the three inputs and one output. Your logic seems correct, i just would like to clearify what i am to do, and and example of the output.