The resistors are in series, so their equivalent resistance is simply the sum of the three resistances,
Then we simply plug in our numbers:
Remember, this is power - the rate at which the energy is being converted. So if we want to look at heat, we can say that 18.52 Joules of heat are being produced every second that current is running through the resistors. For example, if you left the circuit connected for 10 seconds, 185.2 Joules of enerygy would be dissipated.
Does this make sense?
"Pure mathematics is, in its way, the poetry of logical ideas."