Understanding the Problem
First, I read the problem to make sure I understood it. Then I picked out important information. It is a good idea to go through the word problem a few times to find data you might have missed. The data I felt was important is in bold letters.
A fireman stood on the middle rung of a ladder, directing water into a burning building. As the smoke lessened, he stepped up three rungs. A sudden flare-up forced him to go down five rungs. Later he climbed up seven rungs and worked there until the fire was out. Then he climbed the remaining six rungs to the top of the ladder and entered the building. How many rungs did the whole ladder have?
I decided the best method to solve the problem would be to make a list of the numbers and add them together. This will tell me how many rungs are above the rung he was standing on.
3 + (-5) + 7 + 6 = 11
If there are eleven rungs above the rung he was standing on there must be eleven below, so I multiplied eleven by two.
11 * 2 = 22
There is no middle rung to twenty-two and the fireman was standing on the middle rung, so I added one for the rung he was standing on.
22 + 1 = 23
The ladder has 23 rungs.
Now try a few on your own.
S. A. Hudson: SHUDSON@nmu.edu.