Answer: 0.395 km
Explanation:
Let Martin distance from the hole be X
On first stroke, his golf ball traveled 4/5 of the distance to the hole. That is 4/5 X
On his second stroke, the ball traveled 79 meters and went into the hole
Total distance covered will be
X = 79 + 4/5X
X - 4/5X = 79
X - 0.8X = 79
0.2X = 79
X = 79/0.2 = 395 meters
How many kilometers from the hole was Martin when he started
X = 395/1000 = 0.395 km