Number of electrons = (total charge) / (charge on each electron)
Number of electrons = (27.88 C) / (1.602 x 10⁻¹⁹ C/e)
Number of electrons = 1.74 x 10²⁰ electrons
Average current = (charge transferred) / (time to transfer the charge)
Average current = (27.88 C) / (0.001 sec)
| Average current | = 27,880 Amperes (Yes. The current is big.)
Note:
That current can be either a positive or a negative number.
The question asks for the current flowing "from the cloud to ground", but it never tells us which direction the electrons are physically moving ... up from ground to cloud, or down from cloud to ground. Real lightning bolts can go either way.