SOLUTION: Ramiro walks to work each morning. During the first minute he walks 80 metres. In each subsequent he walks 90% of the distance walked during the previous minute. The distance bet

Algebra ->  Sequences-and-series -> SOLUTION: Ramiro walks to work each morning. During the first minute he walks 80 metres. In each subsequent he walks 90% of the distance walked during the previous minute. The distance bet      Log On


   



Question 1096827: Ramiro walks to work each morning. During the first minute he walks 80 metres. In each subsequent he walks 90% of the distance walked during the previous minute.
The distance between his house and work is 660 metres. Ramiro leaves his house at 08:00 and has to be at work by 08:15. Explain why he will not be at work on time.

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
This is a geometric series with a ratio of 0.9
The sum of 15 terms (until 8:15) is a1(1-r^n)/(1-r), where a1 is the distance walked the first minute, r=0.9 and 0.9^15=0.2059
Sum=80(0.7941)/0.1
= 635.28 m < 660 m.