Using our problem to make a rectangular array, we know that we are going to use a total of  squares, and one dimension of the rectangular array is going to have  squares, we'll make that the width. Our answer will be how many squares high the rectangle array is, or the height. 

We can start with  squares and keep adding  on top of the previous  until we've used all  squares. Our rectangular array is  squares high with  squares left over, which is our remainder. 

Using our problem to make a rectangular array, we know that we are going to use a total of  squares, and one dimension of the rectangular array is going to have  squares, we'll make that the width. Our answer will be how many squares high the rectangle array is, or the height. 

We can start with  squares and keep adding  on top of the previous  until we've used all  squares. Our rectangular array is  squares high with  squares left over, which is our remainder. 

In order to figure out how many cookies each person can get, you have to divide 36, which is 3 dozen, by 15. 

You could also figure out how many groups of 15 there are. 

 The first 15, so everyone can get at least one cookie.

 The second 15 cookies, so everyone can get two cookies. 

 There are 6 cookies left over. 

A factor is a number that is multiplied by another number to produce a given number. 

In this case, the unknown factor is the number multiplied by  to get . 

Think: What times  equals 

A factor is a number that is multiplied by another number to produce a given number. 

In this case, the unknown factor is the number multiplied by  to get . 

Think: What times  equals 

Using our problem to make a rectangular array, we know that we are going to use a total of  squares, and one dimension of the rectangular array is going to have  squares, we'll make that the width. Our answer will be how many squares high the rectangle array is, or the height. 

We can start with  squares and keep adding  on top of the previous  until we've used all  squares. Our rectangular array is  squares high. 

The opposite of multiplication is division. In order to find the missing piece of this multiplication problem we can divide. 

To solve this division problem, we can think of it as a missing factor problem. 

Think: What times  equals 

When we are dividing, we are splitting things up into groups. For this problem, we can think of this as we have  items and we want to split them up equally into  groups. We are solving for the number of items in each group. 

We can draw  circles and start putting the  items, in this case triangles, into each circle equally. 

Our answer is the number of items in  group. In this case, there are  triangles in each of the groups so our answer is . 

When we have a set of something that we are splitting up into groups, we divide. In this case, we are splitting up cookies into containers. We have  cookies that we are dividing into containers. Each container holds  cookies, so we divide  by  to find out how many containers we can fill. We will let  represent the number of containers that we can fill. 

We drop the remainder of  because the question asks how many containers we can fill completely.