Question

How much current is in a circuit that includes a 9-volt battery and a bulb with a resistance of 12 ohms?

Answer 1

Current = (voltage) / (Resistance)

If those are the ONLY things in the circuit, then

Current = (9 volts) / (12 ohms)

Current = 0.75 Ampere

Answer 2

V = IR

Where v is voltage I is current and r is resistance

So

V = 9

R = 12

V/R = I

9/12 = I

I = 0.75 A