Question

How can three resistors of resistance 2OHM 3OHM AND 6OHM be connected for total resistance of 4OHM And 9ohm

Answer 1

For 40 ohm:-----connect 20ohm in series with (30ohm and 60ohm in parallel)

for 9ohm:---------we cannot get 9ohm with these three combination because

the least resistance we can get is 10 ohm below this we cannot achieve.