If w, x, y, and z are positive real numbers such that w + 2x + 3y + 4z = 8 then what is the maximum value of wxyz?
The correct answer is 2/3 because you get (w+2x+3y+4z)/4 >= 4rt(24wxyz) which becomes 8/4 >= 4rt(24wxyz) so you get 2^4 >= 24wxyz. This simplifies to 16/24=2/3=wxyz.
You use the AM-GM inequality which says (a_1+a_2+a_3+...+a_n)/n >= nrt(a_1*a_2*...*a_n). Here's the art of problem solving article https://artofproblemsolving.com/wiki/index.php/Arithmetic_Mean-Geometric_Mean_Inequality
I agree my answer is not correct but there is not enough information on that linked page for your answer to be reached.
You should not be dividing by 4 you should be dividing by 10. (to get the arithemtic mean)
the numbers are w,x,x,y,y,y,z,z,z,z, There are 10 numbers.
Perhaps you would like to provide more working or another link address that you used.