First, count the distance in 3 days
distance = 3 × distance each day
distance = 3 × 4 km
distance = 12 km
Second, convert the distance to meter
1 km is equal to 1,000 m
distance = 12 km
distance = 12 × 1,000 m
distance = 12,000 m
Third, determine the number of laps
laps = distance/each lap
laps = 12,000/400
laps = 30
Kali run 30 laps in 3 days