Let’s Learn!

Think About It!

Goal: Create related facts to find the unknown number in division equations.

Logan sold a total of 72 horseshoes today. Each customer purchased 8 horseshoes. How many customers did Logan have?

We can find the number of customers by finding the unknown divisor in this equation:

72 divided by ? equals 8. The question mark is labeled as the unknown divisor.

We can use a related fact to find the unknown divisor. Related facts use the same three numbers. This division equation has the numbers 72 and 8. Just slide the 8 into the unknown divisor’s place and slide the question mark into the quotient’s place.

72 divided by ? equals 8. The question mark is the unkown divisor. It becomes the quotient. 8 is the quotient. It becomes the divisor. 72 divided by 8 equals ?

You can solve this division equation using any division strategy:

Repeated Subtraction

72 - 8 - 8 - 8 - 8 - 8 - 8 - 8 - 8 - 8 - 8 = 0

Subtract 8 from 72 nine times.

Array

This array has 8 rows of 9 dots.

Picture

This picture has 8 groups of 9.

Equal Groups

There are 8 equal groups of 9.

Nice work! Each strategy shows a quotient of 9. Now we will just replace the unknown divisor with the number 9.

72 divided by ? equals 8. Reorganized to 72 divided by 8 equals 9.

Logan had 9 customers today!

It is the next day, and Logan has sold the rest of his horseshoes!

He had 6 customers, and each customer bought 10 horseshoes. How many horseshoes did Logan start with today?

We can find the number of customers by finding the unknown dividend in this equation:

? divided by 6 equals 10. The question mark is labeled as the unknown divided.

We can use a related multiplication fact to find the number of horseshoes Logan started the day with. Remember, related facts must use the same numbers.