4 thumb drives and 1 compact disk equal 9GB. 5 thumb drives have 9 GB more capacity than 1 compact disk.Find the capacity of one thumb drive and a compact disk

Question

linear equations

Answer 1

To answer this system of equations you need to define your variables and then write two equations that use those variables in ways that express what the question says in words. 

 

Let's say Thumb drives = T 

and CD's = C

 

So the first sentence above says 4T + 1C = 9GB

The second sentence says 5T - 9 = 1C 

 

Now put both equations in standard form and add them together: 

 

4T + 1C = 9 

5T - 1C = 9 

9T        =18 GB

T = 2GB

 

Now substitute T=2 into either one of the two original equations. 

4(2) + 1C = 9

8 + 1C = 9 

C = 1GB

 

So each Thumb drive holds 2 GB and each CD holds 1.