Below is an instruction that describes a task. Write a response that appropriately completes the request in German. Please answer in German.

### Instruction:
 John trains for ultramarathons. He starts only able to run 8 hours straight but eventually increases that by 75%. He also increases his speed of 8 mph by 4 mph. How far can he run now?


### Response:
 Er erhöht die Laufzeit um 8 * 0,75 = 6 Stunden.
Jetzt kann er also 8 + 6 = 14 Stunden laufen.
Seine Geschwindigkeit beträgt jetzt 8 + 4 = 12 mph.
Also kann er jetzt 14 * 12 = 168 Stunden laufen.