Answer: 5.7 km
Step-by-step explanation: take first day as day 1
day 1, she walked 600 m
day 2, she increased her walk by 300 m
that means, day 2 = 600 m + 300 m = 900 m
day 3, she increased her walk by 300 m again
that means, 900 m + 300 m = 1200 m
so we can deduce a formula to calculate her expected walk for the remaining days
day n = initial distance + increased distance (n - 1)
where; n is the no. of day we are looking for
initial distance is the distance walked on day 1
increased distance is the distance added on each day
so, if day 3 = 600 m + 300 m (2) = 600 m + 600 m = 1200 m
∴ day 18 = 600 m + 300 m (17) = 600 m + 5100 m = 5700 m
now, we convert 5700 m to km.
1000m=1km
5700m= 5.7km
so, on 18 days, susie will walk 5.7 km
