Im not really sure but i thinki think it is 
        
             
        
        
        
If you divide 2380 by 4, it will give you 10% of the whole:
1380/4=345
Then you can times 345 by 6 To find the 60%:
345*6=2070
PS Please check my calculations with a calculator as I worked these out in my head.
        
             
        
        
        
I think the answer is 17%
        
             
        
        
        
6= 4(z+9)/y+2
6y +12 =4(z+9)
6y=4(z+9) -12
y=(4(z+9)-12)/6
y=2z+18-6/3
y=2z+12 /3
        
             
        
        
        
Answer:
278.25 cm2
Step-by-step explanation:
If the width of the rectangle is x (cm), as the length is 8cm longer, so that the length of the rectangle is: x + 8 (cm).
In the attached image, we can see the length of each side. Total length of the sides are 90 cm. 
=> (x + x + 8) + x + 8 + (x+8) + (x + x + 8) + x + 8 + (x +8) = 90
=> 8x + 48 = 90 
=> 8x = 90 - 48 = 42 
=> x =42/8 = 5.25 (cm)
=> The width of the rectangle is 5.25cm 
=> The length of the rectangle is: 5.25 + 8 = 13.25 cm
=> The area of one rectangle is: Length x Width = 5.25 x 13.25 = 69.5625 cm2
As the 8-sided shape is made from 4 rectangles, so that:
Area of 8 sided shape = 4 x Area of the rectangle = 4 x 69.5625 = 278.25 cm2