5th grade math: "The model shown represents a division equation."

[dpalmer2023]

I am a child of the 70s so I have no idea how to solve this math problem! Can someone walk me through it, maybe even send me a link to a video that can explain it to me?

 

[stapel]

I am a child of the 70s so I have no idea how to solve this math problem! Can someone walk me through it, maybe even send me a link to a video that can explain it to me?

I've never before seen this, and am not at all certain of my answer, but--

Here are some links that *might* help:

* ThirdSpaceLearning
* SmarTick
* SmathSmarts

The grid on the right-hand side of your paper (the one labeled "1 whole") says that each square in the grid represents 1/100. Thirty-two squares are shaded, which represent 32/100 = 0.32.

If this were a multiplication exercise, I would guess that the equation would be something along the lines of (the width) times (the height), or (0.4)*(0.8) = 0.32. Since this is a division exercise, I would guess that the corresponding division equation is what they're looking for.

But that's just a guess.

 

[Dr.Peterson]

I am a child of the 70s so I have no idea how to solve this math problem! Can someone walk me through it, maybe even send me a link to a video that can explain it to me?

To be sure, you'd really need to see what kind of examples have been done in the class; is there more than this sheet?

But I'll show you how I think through it.

​

The key on the right says that the entire 10x10 square represents 1; so each little square represents 0.01.

The gray area on the left contains 8x4 = 32 little squares, so it represents 0.8 x 0.4 = 0.32.

So as a multiplication, it could be 0.8 x 0.4 = 0.32; as a division, that could be either 0.32 / 0.4 = 0.8, or 0,32 / 0.8 = 0.4.

Or, since they have, if you look carefully, divided the area into 4 vertical strips, you could also think of it as 0.32 / 4 = 0.08, where we've divided 0.32 into 4 equal parts, each containing 8 little squares.

Now, do any of those match the choices?

​

Yes, B looks good. (If we ignore the key, A could also be reasonable.)

My guess is that they are learning about dividing decimals by whole numbers, since all four choices involve division by 4; so the student would be expected to ask, what is being divided into 4 equal parts? And using the key, that has to be 0.32 / 4 = 0.8, which is the size of each of those parts.

I'd search for pages about models of decimal division, but it's likely that would cover any of several different "area models". Does the school or teacher provide any information for parents, as some do, to help them see what is being taught? Or do you know the name of the curriculum, so you could search for anything they provide for parents?