Implement combination operations in two multi-dimensional matrix

Dear all;

I have a two multidimensional matrix of each 4-by-24.I wanted to performe the combination of the two matrix in row and pefrom that combnation for the number of times equal with the column,let me make it more clear as:

 M1=4*ones(4,24);
M2=2*ones(4,24);

Then,I want to calculate the value of A for the combination of rows in M1 and M2,and that calculation should be repeated for 24 times

A=M1+0.5*M2

This is my try

[X,Y]=ndgrid(M1,M2);
for c=1:numel(X)
    for t=1:24
        A(c,time)=M1(c,time)+0.5*M2(c,time)
    end
end

Can anyone help me on this regard?thanks