need help with two word problems involving four square...

[tigerpawz74]

Hi, thanks for your help!
First of all, what is "four square" and how do you use it to solve problems?
I have two problems.

The directions state: Use a four square to solve these problems.

(1) Amy is going on a 120-mile trip. She traveled for 60 miles at 30 miles per hour. How fast will she have to travel for the rest of the trip to average 40 miles per hour?

(2) Erin, Brandon, an Chelsea are standing in a straight line for a picture. How many different ways can these children stand in line?

 

[soroban]

Re: need help with two word problems involving four square..

Hellom tigerpawz74!

First of all, what is "four square" and how do you use it to solve problems?

If you don't know and your teacher didn't tell you, I certainly don't know!

(1) Amy is going on a 120-mile trip.
She traveled for 60 miles at 30 miles per hour.
How fast will she have to travel for the rest of the trip to average 40 miles per hour?

This can be solved by pure "common sense".

She wants to average 40 mph for the entire 120-mile trip.
Then she must drive it in exactly 3 hours . . . right?

She already drove the first 60 miles at 30 mph, using up 2 hours.

Hence, she must drive the last 60 miles in exactly 1 hour.

Therefore, her speed must be . . . ?

 

[tigerpawz74]

Thanks for your attempt to help, however, the question didn't envolve hours driven, the question asked how fast she'd have to travel for the rest of the trip to average 40 miles per hour. And I'm not a student, I'm trying to help a friend who has a fifth grader needing help with her homework. The instructions on the paper were exactly as I stated. I've looked in every math book I have from basic math through Algebra 2 and Trig and can't find what four square means.

 

[Denis]

Seems to be a brand new method devised for kids;
do a http://www.google.com search on "four square method".

No, I'm not interested in learning it

 

[stapel]

Thanks for your attempt to help, however, the question didn't envolve hours driven....

If it involved distances and rates, then it likely involved the time required to cover those distances at those rates.

No, the exercise didn't ask, as the final answer, for the number of hours driven. But did you read the solution provided to you? By using the hours (and common sense), the answer is easily obtained -- unless you don't know how to find the rate required to cover sixty miles in one hour...? :shock:

Eliz.

 

[tigerpawz74]

Eliz and Denis.....

Thanks for your help...

Eliz, yes, you can work it out like that, however, the question said to use a four square method. That is what I am not clear on. I've never heard of this method and I was hoping someone might have knowledge on how to use it. I do appreciate your help, though!

Denis, I tried the Google search and I'm still looking at that, I can't find what I need but I'm still looking. Thanks!

 

[happy]

I suggest asking your teacher what the "four square method" is, since he/she assigned it to you. You're in the class, not us. It's your job to get all directions, not ours.

 

[soroban]

Hello, tigerpawz74!

Thanks for your attempt to help,
however, the question didn't envolve hours driven,
the question asked how fast she'd have to travel for the rest of the trip to average 40 miles per hour.
Did you read the last line of my reply?

I did a search on "Four Square Method" and every site raved about the marvels
. . of the Four Square Method for writing . . . none gave any mathmatical examples.
But all of them offered to <u>sell</u> me the entire series.

And I really don't see how it can be applied to mathematical problems . . . especially #2.

(2) Erin, Brandon, and Chelsea are standing in a straight line for a picture.
How many different ways can these children stand in line?

For the position on the far left, there are \(\displaystyle 3\) choices: Erin, Brandon, or Chelsea.

Once the first position is filled, there are 2 choices for the second position (either of the other two children).

Then there is 1 choice for the third position (the last remaining child).

Therefore, there are \(\displaystyle 3\,\times\,2\,\times\,1\:=\:6\) ways.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Maybe a fifth-grader may be expect to simply <u>list</u> the possible orders.

They would be: \(\displaystyle \,EBC,\;ECB,\;BEC,\;BCE,\;CEB,\;CBE\)

See? . . . six ways.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

The Four Square Method says: write a statement in the center of a square.
. . Then write three related statements in three of the corners.
. . Then write a conclusion in the fourth corner.

Somehow (?) this is supposed to help me organize my thoughts.
. . Evidently, I was under the delusion that I knew how to do Math . . .


Please ask your friend to ask his/her fifth-grader to ask his/her teacher
. . what his/her version of the Four Square Method means,
. . and how it is to be applied to math problems.

 

[Denis]

The Four Square Method says: write a statement in the center of a square.
. . Then write three related statements in three of the corners.
. . Then write a conclusion in the fourth corner.

C'mon Soroban, eezy:

Center: E, B and C wanna get their pictures taken

Corner1: E can be 1st in line 2 ways: EBC and ECB
Corner2: B can be 1st in line 2 ways: BEC and BCE
Corner3: C can be 1st in line 2 ways: CEB and CBE

Corner4: Therefore, they can stand a total of 6 different ways.

[...and someone is now a millionaire due to this invention]

 

[tigerpawz74]

thanks for your help

Thank you all for your replies to my questions. I have a copy of the actual paper the teacher sent home with the fifth grader, there were no other instructions on it, so I don't know how she expected the students to work these out. I do appreciate your help. I hope you all have a great weekend!