How should three capacitors of capacitances `3muF,3muF" and "6muF`, be connected to get an equivalent capacitance of `5muF`?

Explanation

For a parallel connection of all the three capacitors, the equivalent capacitance `= 3+3+6 = 12muF` , it is greater than `5muF`.
Again, for a series connection, if the equivalent capacitance is `C_s`, then `(1)/(C_s)= (1)/(3)+(1)/(3)+(1)/(6)= (5)/(6)`
or, `C_s = (6)/(5)= 1.2 muF`, it is less than `5muF`.
So, the above two connection are not applicable. Then, the following four arrangements are possible.

Now, for the arrangement(a), equivalent capacitance is clearly greater then `6muF` , so it cannot be `5muF`.
For the arrangement(b), equivalent capacitance
`=((6+3)xx3)/((6+3)+3)= 2.25muF`
For the arrangement (c), equivalent capacitance `= ((3+3)xx6)/((3+3)+6)= 3muf`
For arrangemnt (d), equivalent capacitance
`=3+(3xx6)/(3+6) = 5muF`
So, the arrangement (d) represents the desired connection.