First, we have to express all the weights in pounds only.
We know that 1 pound is equivalent to 16 ounces. Let's transform each ounce.
[tex]6oz\cdot\frac{1lb}{16oz}=\frac{6}{16}lb=\frac{3}{8}lb[/tex]Then, we sum to the first weight.
[tex]5+\frac{3}{8}=\frac{40+3}{8}=\frac{43}{8}=5.375[/tex]Now, we transform the ounces of the second birth.
[tex]10oz\cdot\frac{1lb}{16oz}=\frac{10}{16}lb=\frac{5}{8}lb[/tex]Then, we sum.
[tex]4+\frac{5}{8}=\frac{32+5}{8}=\frac{37}{8}=4.625lb[/tex]Then, we sum.
[tex]4+\frac{7}{8}=\frac{32+7}{8}=\frac{39}{8}=4.875lb[/tex]Then, we sum.
[tex]5+\frac{1}{8}=\frac{40+1}{8}=\frac{41}{8}=5.125lb[/tex]At last, we have to sum all the pounds.
[tex]5.375+4.625+4.875+5.125=20[/tex]Hence, the total weight in pounds is 20.