Answer:
30 Jackets
90 Hooded Sweat Shirts
240 Shirts
Step-by-step explanation:
Given
Represent each item with their first letters;
[tex]J +H + S = 360[/tex]
[tex]50J + 30H + 15S = 7800[/tex]
[tex]S= 8J[/tex]
Required
Get the value of J, H and S
Substitute 8J for S in the first two equations
[tex]J + H + 8J = 360[/tex]
[tex]H + 9J = 360[/tex] --- Make H the subject
[tex]H = 360 - 9J[/tex]
[tex]50J + 30H +15*8J = 7800[/tex]
[tex]50J + 30H +120J = 7800[/tex]
[tex]170J + 30H = 7800[/tex]
Divide through by 10
[tex]17J + 3H = 780[/tex]
Substitute [tex]H = 360 - 9J[/tex]
[tex]17J + 3(360 -9J) = 780[/tex]
[tex]17J + 1080 -27J = 780[/tex]
Collect Like Terms
[tex]17J -27J = 780 - 1080[/tex]
[tex]-10J = -300[/tex]
Solve for J
[tex]J = \frac{-300}{-10}[/tex]
[tex]J = 30[/tex]
Recall that: [tex]H = 360 - 9J[/tex]
[tex]H = 360 - 9 * 30[/tex]
[tex]H = 360 - 270[/tex]
[tex]H = 90[/tex]
Substitute values for H and J in [tex]J +H + S = 360[/tex]
[tex]30 + 90 + S=360[/tex]
[tex]S = 360 - 30 - 90[/tex]
[tex]S = 240[/tex]