Who Can Explain This "Second Grade" Math Problem?

Yardlie · ‎03-10-2010

I didn't see this anywhere else on the boards, so I'm asking here. If it is on the boards, please direct me to it. This question has been all over online the last couple days. Supposedly, it is a second grade math question...but it is stumping most people. Now, I was not a math major, but I did go through one semester of calculus. Maybe my mind is beginning to go. What I want to know is, what did you get for an answer...and since when did they start teaching algebra in second grade?

Question: “There are 49 dogs signed up to compete in the dog show,” The question begins. “There are 36 more small dogs than large dogs signed up to compete. How many small dogs are signed up to compete?”

My obvious solution was the same as many other people: 49 total dogs minus 36 small dogs must equal 13 large dogs...so that leaves 36 small dogs. Seemed too easy, but it is a second grade question!!!

The correct answer I found online is:

What you’re doing is trying to solve for x. Think of large dogs as “x” and small dogs as “y.”

49 = x+y and y = x+36

So, combine the two equations and you get:

49 = x + x+36

49 = 2x + 36

13 = 2x

x = 6.5

y = 42.5

?????!!!!! Anyone care to clarify? (1) Why isn't the answer 13? (2) Since when do second graders solve for "x"? "How can you have a half a dog?" Thanks!

A kind gesture can reach a wound that only compassion can heal. ~~ Steve Maraboli

WenGirl42 · ‎07-05-2012

wrote:
I didn't see this anywhere else on the boards, so I'm asking here. If it is on the boards, please direct me to it. This question has been all over online the last couple days. Supposedly, it is a second grade math question...but it is stumping most people. Now, I was not a math major, but I did go through one semester of calculus. Maybe my mind is beginning to go. What I want to know is, what did you get for an answer...and since when did they start teaching algebra in second grade?

Question: “There are 49 dogs signed up to compete in the dog show,” The question begins. “There are 36 more small dogs than large dogs signed up to compete. How many small dogs are signed up to compete?”

My obvious solution was the same as many other people: 49 total dogs minus 36 small dogs must equal 13 large dogs...so that leaves 36 small dogs. Seemed too easy, but it is a second grade question!!!

The correct answer I found online is:

What you’re doing is trying to solve for x. Think of large dogs as “x” and small dogs as “y.”
49 = x+y and y = x+36
So, combine the two equations and you get:
49 = x + x+36
49 = 2x + 36
13 = 2x
x = 6.5
y = 42.5

?????!!!!! Anyone care to clarify? (1) Why isn't the answer 13? (2) Since when do second graders solve for "x"? "How can you have a half a dog?" Thanks!

Well I can't help with questions 2 or 3. But there can't be 13 small dogs, because then there would be more large dogs than small to make 49. And there can't be 36 small dogs, because that's not 36 more than the number of large dogs (given as 13). If there are 13 large dogs, you'd need 13+36=49 small dogs for that to be true. Which would give you 62 total dogs. Isn't math fun?

blackhole99 · ‎08-22-2013

It's a physical problem that can't be solved because you can't have half a dog. You can solve it for the numbers, but it doesn't make physical sense. It's just to show you how to solve a linear equation, but doesn't make sense physically. No wonder the kids hate math right out of the box.

sidsmom · ‎11-25-2011

My 2nd Grade detailed personality would be the one asking,

What kind of dogs were the small ones?

What kind of dogs were the big ones?

Where was this dog show?

What group were they competing in?

....and all the time the teacher would be patiently telling me,

’ that doesn’t matter with this situation’...and I would continue

asking the ‘backstory’ questions...I just have to know the whole story.

I like details but not analytical details.

I just wanna pet the dogs.

luvmybeetle · ‎08-10-2013

OK I get it but I think I'm confused. My grandson did have this kind of math in the second grade. Even my daughter couldn't help him.

nomless · ‎03-10-2010

@Yardlie

The number 13 answers the question "There are 49 dogs in the show. 36 are small dogs. How many are large?" .(13 +36 = 49)

But that is not the question that was asked.

The question is "Total dogs = 49, and there are 36 more small dogs than large dogs. How many dogs of each type?"

Note that if you use your answer 36 small and 13 large, although there are 49 total dogs, there are only 23 more small dogs than large dogs, not 36. (36-13=23.)

2x + 36 = 49 is the correct equation. Each group has x dogs and the small dog group has 36 additional dogs.

So solving for x, 2x=13, and x = 6.5

So the number of large dogs = 6.5

And the number of small = 6.5 + 36 = 42.5

42.5 + 6.5 = 49, the total number of dogs

And 42.5 - 6.5 = 36. Now there are 36 more small dogs than large dogs.

It was a bad choice to use dogs for this example because you can't have half a dog. Sandwiches would have been a better object to use.

WenGirl42 · ‎07-05-2012

@nomless I would like to be a judge at the sandwich show

nomless · ‎03-10-2010

wrote:
@nomless I would like to be a judge at the sandwich show

@WenGirl42, lol.😂

KitTkat · ‎11-07-2017

To be even more confusing, what if all the large dogs ate half the sandwiches, leaving the remaining sandwiches for the small dogs. How many sandwiches did the small dogs eat?

I remember questions like these, but weren't they more fifth or sixth grade questions?

sidsmom · ‎11-25-2011

wrote:
To be even more confusing, what if all the large dogs ate half the sandwiches, leaving the remaining sandwiches for the small dogs. How many sandwiches did the small dogs eat?

I remember questions like these, but weren't they more fifth or sixth grade questions?

I like the way you think!

What kind of sandwiches? Hee