Real World Problems
Pete is 15 years older than Nick. Nick is 18 years younger than Howie. If Pete is 18 years old, how old is Howie?
Try this problem with one of your classes, maybe use it as a warmup problem. Have the studetns write the steps to solving this problem. Share their responses along with how you would teach this concept.
posted by Mrs. Kimball @ 4:26 PM
7 Comments:
I used this problem with my 7th grade class. We were currently exploring algebraic expressions so I asked them to create one using the written expression given. The class first came up with equations to describe each boy. Pete = 15 + N, Nick = H - 18. Then they took the information about Pete being 18 and set that equal to Pete's previous equation 15 + N = 18. They solved for N by doing inverse operations and found that N = 3. They plugged that into the second equation and found that H = 21, therefore Howie is 21 years old. I had to assist them here and there and we did complete this as a class.
test
Thanks Concetta for trying this with your class!
I taught this the exact same way to my PreAlgebra class while teaching algebraic expressions. Some students automatically went straight to algebra to solve while some worked in their head and others did guess and check. It is funny b/c i always think to do things algebraically and sometimes I don't understand why you would do it any other way!
The students in my class created a visual of the students. They placed the people in a line according to where their ages were. Then they subtracted to find out how old Howie was.
I would go through the sentences with the students and turn them into equations. First we would assign variables to all the names. P=Pete, N=Nick, and H=Howie. So according to the first sentence P=15+N. The Second sentence reads N=H-18. In the third sentence they tell us that P=18. So we went back and plugged in 18 for P in the first equation and solved algebraically. Our answer was N=3. To find Howie's age we used the second equation and substituted N for 3. 3=H-18. We also solved this algebraically and found that H=21.
My students used Pete's age to first determine Nick's age. Then they added 18 to Nick's age to finally get Howie's age. Some drew a picture to help them to visualize the situation as they worked.
Post a Comment
Subscribe to Post Comments [Atom]
<< Home