From quick rough working.. I got 17.5 ohms for the total of the circuit.
So, starting from right to left... I got.
10 ohms in parallel with 20 ohms.
This gave me 6.666667 ohms in parallel with another 20 ohms
which gave me 5 ohms, which is in series with 20 ohms.
This gives 25 ohms, which is now in parallel with 25 ohms.
This gives 12.5 ohms, which is now in series with the 5 ohm resistor, and totals 17.5 ohms.