A uniform 3.05 kg board of length L = 1.58 m overhangs the edge of a table by x = 0.32 m. If a 4.87 kg block is placed on the board, what is the maximum distance d from the edge of the table that the block can be placed without tipping the board?

Question

A uniform 3.05 kg board of length L  =  1.58 m overhangs the edge of a table by x  =  0.32 m. If a 4.87 kg block is placed on the board, what is the maximum distance d from the edge of the table that the block can be placed without tipping the board?

so you have to solve for d. 
(L/2)= location of centre of gravity
Mb= mass of board
Mw= mass of the block

The formula i have been trying to use 
(First line is all over the second line)
 D=  X(Mb + Mw)-(L/2) (Mb) +X 
                         Mb+Mw

bobpursley · Answer

Sum moments about the edge of the table.
D is the distance over the edge
d is the distance from the edge to center of mass of the board.

3.05d-4.87D=0

D= 3.05d/4.87

but d= 1.58/2-.32

That does not look like your answer.