## Tuesday, July 29, 2014

### Pro-Bot drives up a steep mountain

Pro-Bot is trying to go up a mountain. But the mountain is so steep that for every 4 miles that Pro-Bot climbs up, it slides back 1 mile. Pro-Bot attempts this 5 times. How far is Pro-Bot from its starting point at the end of the 5th attempt?

Write a program to trace the path taken by Pro-Bot. Use 1 cm to represent 1 mile in your program.
Do you see a repeating action here? If yes, can you use a Repeat Loop in writing this program?

After tracing the path with Pro-Bot, use a ruler to measure the distance traveled to check if it matches the distance that you calculated.

I designed this question to let the children map a word problem to a math problem and finally to a computer program. It represents a real-life problem solving scenario which includes reading and understanding a word problem, identifying recurring patterns in it, applying mathematical concepts to the problem, scaling of quantities to reasonable sizes and finally coming up with the solution to the problem in the form of a computer program.

The solution is a very simple program:

Rpt 5 [
Fd 4
Bk 1
]

The total distance traced by Pro-Bot is 15 cm.