("G" is Grayson Wheatley; "S" is the student.)
G – Let’s look at this problem. If you would read this one here please.
S – A swimming pool in the shape of a rectangle is surrounded by 3 feet of walkway. The pool is 23 feet wide and 32 feet long. How long would the fence be that just encloses the walkway and the pool?
G – Take your time to think what it means.
S – I’ll draw a rectangle and 3 feet wide surrounded by 3 feet wide walkway and then the pool is 23 feet wide and 32 feet long. So they just want to know how long it is.
G – I’m going to a hardware store to buy a fence and I want to know how much fence to order.
S – OK
G – Tell us what you have done here.
S – I was trying to find the area of the rectangle which is the pool.
G – And you did that by multiplying 23 times 32 and you came up with 736. OK.
S – And then, I am not sure, just 3 times 3 equal 9.
G – Just try anything you like. So, where is the fence that we are going to build in terms of your picture here? Where would the fence be?
S – It would be around the outside.
G – Yeah, that’s where it would be and we want to know how much fencing to buy.
S – OK, lets try 23 plus 3, 26, and 32 plus 3 cause it is all the way around. The let’s to that instead. OK, let’s try about…OK, I took the 23 and added the 3 and the 32 and added the 3 and I multiplied the sums and got 850.
G – Yes.
S – So I think that’s…
G – So when I go to the hardware store, I should order 850 feet of fencing and that would just do it.
S – I think so.
G – OK, so 850 feet would be the distance around the pool. I understand just how you thought about it. Thanks a lot.