Answer:
The total resistance is 
Step-by-step explanation:
Attached please find the circuit diagram. The circuit is composed by a voltage source and two resistors connected in parallel:
and
.
First step: find the total current
For finding the current that the voltage source can provide, you must find the current consumed by each load and then add both. To do that, take first into account that the voltage is the same for both resistors (
and
).
The total current is:


Now, the total resistance (
) would be the voltage divided by the total current:

If you replace
by the expression obtained previously, the total resistance would be:

After simplifying the terms you should get:

Now, you must replace the values of the resistors:

Thus, the total resistance is 