# making dot arrays

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what are the numbers calleed that we cant use in 2 - row arrays

I'm curious to know what class is making dot-arrays? If you can give some kind of answer I'll try google searches to find and answer.
It's becoming apparent to me that the term array is being used with some specialized meaning I'm unaware of.
I also see now that at least 6 people have posted that question here, unsuccessfully too. Can you provide just a little more info for us?

my daughters 5th grade is doing arrays in math class

what do we call the number that cannot be arranged into 2 row arrays /

what do we call the numbers that cannot be arranged into 2-row arrays?

Okay, after doing a little research I think I understand how these terms are being used here. However, considering that I've gotten 0 feedback to the requests I've made, keep in mind that this is a guess on my part.
This concept of dot arrays and numbers appears to come from elementary math. Specifically, the arrays are being associated with the factorization of the positive integers.
We might think of them as rectangular grids of squares corresponding to the factorization of a number. The number 12 e.g., can be written as 4x3 and 2x6.
In the simplest form primes correspond to 1 row arrays. They cannot be written as any other product than 1xP for a prime P.
This means that two row arrays correspond to the even numbers and those that cannot be written as two row arrays are the odd numbers.
Does this make sense?

what do we call the numbers that cannot be arranged into 2-row arrays?
hurry && get back to me
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How do you make a 14-dot array that has exactly two rows?

What are the numbers that cannot be arranged into 2-row arrays called?

how do you make a 14 dot array that has exactly two rows

• making dot arrays - ,

I am still trying to figure out how to make a two row array myself. From the looks of it, you are right. Simply making a rectangular shape should do it. I do know that numbers that can't be arranged into 2-row arrays are called "odd numbers" while ofcourse what can is called "even numbers". Apparently this is yet another brilliant idea from the board of education to teach our kids division!

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wid you plise helr me bacause its emportent

• making dot arrays - ,

hi my name is hakiza so i ned help for Making Dot Arrays tath my homework

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i don no

• making dot arrays - ,

i don't no

• making dot arrays - ,

Thank you for your answer. It seems like my son just got the same homework sheet with no explanation for it. So it saved our day. Now it makes sense.

• making dot arrays - ,

i don't no

• making dot arrays - ,

Numbers that CAN be made into a 2-row dot array are EVEN numbers (2,4,6,8,etc). Those that CANNOT are called ODD (1,3,5,7). in other words, if the question is asking you to make a 2-row array, it wants you to divide the number by two and make 2 rows of X dots.

Example - Make a 2-row array for the number 20.

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Hope that helps.