How long is the thrid section?

Question

a bridge is divided into 3 sections. The first section is 1/8 the length of the third section. The second section is 1/2 the length of the thrid section. The bridge is 320 feet in length. How long is the thrid section?

Answer 1

x = length of 3rd section

x/2 = length of 2nd section

x/8 = length of 1st section

 

x + x/2 + x/8 = 320 feet

 

Can you solve for x and finish from here?