29.Find the ratio of sales of X, Y and Z.
[tex]1100\colon1900\colon2500=11\colon19\colon25[/tex]Let the common multiple be x.
So it follows:
[tex]\begin{gathered} 11x+19x+25x=700 \\ 55x=700 \\ x=\frac{140}{11} \end{gathered}[/tex]Therefore X has to pay 11x=$140.
Option A is correct.
30.If the charge is increased to $1500 then it follows:
[tex]\begin{gathered} 55x=1500 \\ x=\frac{300}{11} \end{gathered}[/tex]So department Z has to pay 25x=$681.82
Option B is correct.