1.
Since the number of skirts is x and the number of dresses is y
Since the cost of the material of skirts is $13.56 and for the dresses is $18.79
Since she only has $80, then the 1st inequality is
[tex]13.56x+18.79y\leq80\rightarrow(1)[/tex]
Since she takes 2 hours for one skirt and 4 hours for one dress
Since she can work only on them for 15 hours
Then the 2nd inequality is
[tex]2x+4y\leq15\rightarrow(2)[/tex]
2.
We will graph the 2 inequalities
The red area represents inequality (1)
The blue area represents inequality (2)
The two lines red and blue intersected at the point (2.29, 2.605)
Then to get the maximum profit she has to make about 2 skirts and 3 dresses
3.
Since she will sell each skirt for $30 and $40 for each dress
The equation is
[tex]S=30x+40y[/tex]
4.
The vertices of the common shaded area are
(0, 3.75), (2.29, 2.605), (5.9, 0)
Substitute them in the equation to find the maximum amount of profit
[tex]\begin{gathered} S=30(0)+40(4) \\ S=\text{ \$160} \end{gathered}[/tex][tex]\begin{gathered} S=2(30)+3(40) \\ S=60+120 \\ S=\text{ \$}180 \end{gathered}[/tex][tex]\begin{gathered} S=6(30)+0(40) \\ S=\text{ \$}180 \end{gathered}[/tex]
Since the greatest amount of selling is $177, then
The number of skirts is 6
The number of dresses is 0
The total amount of profit is
[tex]\begin{gathered} P=160-4(18.79) \\ P=\text{ \$}84.84 \end{gathered}[/tex][tex]\begin{gathered} P=180-[2\times13.56+3\times18.79] \\ P=\text{ \$}96.51 \end{gathered}[/tex][tex]\begin{gathered} P=180-6(13.56) \\ P=\text{ \$}98.64 \end{gathered}[/tex]
The greatest profit with 6 skirts and 0 dresses
The total amount of profit is $98.64