ATOT, are you smarter than my 3rd grader?

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busydude

Diamond Member
Feb 5, 2010
8,793
5
76
Possibly by division...

row 2 is 2 pets and 2 owners...2/2=1
row 4 is 4 pets and 2 owners...4/2=2
row 6 is 9 pets and 3 owners...9/3=3

If that's it this should not be presented in the third grade

row 6 is 6 pets and 2 owners.. 6/2=3
 

AMCRambler

Diamond Member
Jan 23, 2001
7,715
31
91
2 owners 3 pets each. Teacher = ID10T error

Goes like this:

First you double what you have, then you remove one owner. Then rinse lather and repeat.
 
Last edited:

MotionMan

Lifer
Jan 11, 2006
17,124
12
81
Owner pattern is 1-2-1-2-1-2
Pets per owner pattern is 1-1-2-2-3-3.

The pattern show there will ALWAYS be either 1 or 2 owners so 3 cannot be the correct answer.

MotionMan (who gets to learn a little more "Singapore Math" every day)
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,601
167
111
www.slatebrookfarm.com
Both answers are equally valid, as are other answers.

Here's a sequence: 1, 2, 4, 8, 16, what's next?
The correct answer for the sequence I'm thinking of is 31. 1 + nC2 + nC4
(connecting n points on the circumference of a circle with chords, what is the maximum number of regions formed by those chords?)

Of course, after my class establishes a pattern & thinks the answer for 6 points is 32 regions, their homework assignment is to draw a circle divided into 32 regions. I'm a jerk. :D :p
 

Fayd

Diamond Member
Jun 28, 2001
7,970
2
76
www.manwhoring.com
This is a problem from my daughter’s homework last night. The teacher contends that her answer is incorrect. Let’s see what answer you get.

Jane wishes to organize a pet parade. Every row in the parade will have some combination of owners and pets. In the 1st row, Jane puts 1 owner and 1 pet. In the 2nd row, Jane puts 2 owners with 1 pet each. In the 3rd row, Jane puts 1 owner with 2 pets. In the 4th row, Jane puts 2 owners with 2 pets each. In the 5th row, Jane puts 1 owner with 3 pets. If the pattern continues, how many owners and pets will there be in the 6th row?

the answer she got was:
2 owners, 3 pets each.

the teacher
crossed out the "2" and wrote "3", making the answer, presumably "3 owners, 3 pets each".

it could be either. more iterations are required to know the pattern.
 

Fayd

Diamond Member
Jun 28, 2001
7,970
2
76
www.manwhoring.com
Both answers are equally valid, as are other answers.

Here's a sequence: 1, 2, 4, 8, 16, what's next?
The correct answer for the sequence I'm thinking of is 31. 1 + nC2 + nC4
(connecting n points on the circumference of a circle with chords, what is the maximum number of regions formed by those chords?)

Of course, after my class establishes a pattern & thinks the answer for 6 points is 32 regions, their homework assignment is to draw a circle divided into 32 regions. I'm a jerk. :D :p
not hard. you never specified the regions had to be equal in area.
 

gorcorps

aka Brandon
Jul 18, 2004
30,741
456
126
IMO this isn't a restricted enough pattern to flat out say one and only one answer is right. The teacher should ask the kid why she chose that answer, and if she had a different pattern that she was following she still gets the concept... so is right.
 

MotionMan

Lifer
Jan 11, 2006
17,124
12
81
IMO this isn't a restricted enough pattern to flat out say one and only one answer is right. The teacher should ask the kid why she chose that answer, and if she had a different pattern that she was following she still gets the concept... so is right.

What pattern results in the number of owners being 3?

MotionMan
 

corwin

Diamond Member
Jan 13, 2006
8,644
9
81
How would 3 be the correct answer? What iteration would lead to that?
Using division...

row 2 is 2 pets and 2 owners...2/2=1
row 4 is 4 pets and 2 owners...4/2=2
row 6 is 9 pets and 3 owners...9/3=3 or 6 pets and 2 owners...6/2=3
 

TecHNooB

Diamond Member
Sep 10, 2005
7,458
1
76
If you're going to state alternatives, please state the alternative and a line of reasoning. It's pointless to say there might be more answers without doing so.
 

gorcorps

aka Brandon
Jul 18, 2004
30,741
456
126
I'd also say that at first I thought I would agree with the teacher, but after thinking again the kid seems more right. If you break it up into 2 separate patterns, owners and pets, you get:

owners: 1,2,1,2,1,?
pets:1, 1-1, 2, 2-2, 3,?

Taking them separately would lead to 2 owners, and 3-3 pets (or 3 each) meaning teacher loses.
 

ioni

Senior member
Aug 3, 2009
619
11
81
It's a trap (trick question)! This thread proves there's no established pattern yet.
 

Mr. Pedantic

Diamond Member
Feb 14, 2010
5,027
0
76
In my experience most primary school teachers are pretty horrible at teaching actual content...maybe the smarter ones teach secondary or tertiary students...?

The teacher is wrong in this case, but the important issue is whether they admit they were wrong and correct the issue. Everyone's wrong once in a while; what matters is how they deal with it.
 

MotionMan

Lifer
Jan 11, 2006
17,124
12
81
Using division...

row 2 is 2 pets and 2 owners...2/2=1
row 4 is 4 pets and 2 owners...4/2=2
row 6 is 9 pets and 3 owners...9/3=3 or 6 pets and 2 owners...6/2=3

Thus there would be no one correct answer. Certainly, the teacher cannot say that 2 is wrong and 3 is right, thus, the teacher is still wrong.

MotionMan
 

gorcorps

aka Brandon
Jul 18, 2004
30,741
456
126
In my experience most primary school teachers are pretty horrible at teaching actual content...maybe the smarter ones teach secondary or tertiary students...?

The teacher is wrong in this case, but the important issue is whether they admit they were wrong and correct the issue. Everyone's wrong once in a while; what matters is how they deal with it.

In my experience elementary school teachers don't like to admit they've been bested by a child.
 

ShawnD1

Lifer
May 24, 2003
15,987
2
81
In my experience most primary school teachers are pretty horrible at teaching actual content...maybe the smarter ones teach secondary or tertiary students...?

The teacher is wrong in this case, but the important issue is whether they admit they were wrong and correct the issue. Everyone's wrong once in a while; what matters is how they deal with it.

Depends what their interest is. I know someone who likes kids, so she's a kindergarten teacher. She's not overly passionate about things like math or science.
Other people teach because they like teaching. I don't really like most people, but I could see myself teaching math and science. My high school chem teacher really seemed to like chemistry and explaining chemistry.
 

AMDZen

Lifer
Apr 15, 2004
12,589
0
76
Either answer is correct really as not enough info was given. The pattern can be interpreted both ways. But who cares? Its third grade, not grad school.
 

zinfamous

No Lifer
Jul 12, 2006
111,864
31,359
146
2 owners, 3 pets each. I think that's what most of you are saying, correct? leaving out the "each", part.

so, also: 2 owners, 6 pets total.