Solve Capacitor Circuit: Calculate ε for C1, C2, C3, C4 & C5

[unhip_crayon]

Homework Statement

In the circuit, C1 = 18.0 nF, C2 = 6.00 nF, C3 = 24.0 nF, C4 = 12.0 nF and
C5 = 72.0 nF. The energy stored in C5 is 256. nJ.
Calculate $$\epsilon$$.

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Homework Equations

q=cv

The Attempt at a Solution

C12=24nF
C34=36nF
C125=18nF
C12345=12nF


q5=q12=q34=(C34)(V34)

V24=5/36

V24=0.1389

lol i donno...can someone help me out. I don't understand this. I know q's are equal in series and V's are equal in parallel but then i get stuck. Please help


Thanks

 

[Redbelly98]

You did well to combine C1&C2, and C3&C4. I think I would not further combine the capacitors, given the specific information given about C5.

Also, here's another relevant equation:
(Energy stored) = (1/2) C V^2