Let’s Learn!
How can we use repeated subtraction to divide?
Goal:
Goal:
Think About It!
Goal: Define repeated subtraction and how it relates to division.
Logan wants to write a story about 30 dragons. He needs equal groups of dragons for 10 quests. We can divide to find out how many dragons are going on each quest!
We divide by splitting up a big group of items and putting them into smaller equal groups. We create a division sentence when we divide. The total number is the first number. It is the dividend. There is a division sign after the dividend. The second number is the divisor. It is the number of equal groups. The quotient is the last number. It is the number in each group and the answer when we divide!
Take a look at the division sentence below. Click on the divisor.
20
🤔 No. This is the dividend.
5
😄 Yes! This is the divisor!
4
🤔 No. This is the answer. It is also called the quotient.
We will use repeated subtraction to help us divide. Repeated subtraction is taking away the same number over and over. That number is the repeated subtrahend. It is the same number as the divisor. The minuend is the first number in a repeated subtraction sentence. We take away the repeated subtrahend from the minuend until we get 0 as the difference Then we will count how many times we took that number away. The number of times we subtracted is the quotient!
20 divided by 5 = 4. 5 is labeled divisor, 20 is labeld
dividend, 4 is labeled quotient. 20 - 5 - 5 - 5 - 5 = 0. 20 is
labeled minuend, 5s are labeled repeated subtrahend, 0 is
labeled difference.
Click on each step below to see how to put the dragons into equal groups!
Dividend: The large number that is being separated into smaller groups.
Divisor: The number of groups that the dividend is separated into.
Equal groups: Objects separated into groups of the same numbers.
This picture shows 30 dragons. That is the minuend. Logan wants the dragons to go on 10 quests. That is the divisor. The quests need equal groups of dragons.
Click Show Me to see the division sentence!
30 \({ \div }\) 10 = ?
30 \({ \div }\) 10 = ?
___ - ___ - ___ - ___ = 0
Subtrahend: The number we take away when we subtract. It is the second number in a subtraction sentence.
Minuend: The number we subtract from. It is the first number in a subtraction sentence.
30 is the dividend. 10 is the divisor. That means 30 is also the minuend. 10 is the repeated subtrahend.
Click Show Me to see the subtraction sentence!
30 - 10 - ___ - ___ = 0
30 - 10 - ___ - ___ = 0
How many times do we need to take away 10 from 30 to get 0?
We can keep subtracting 10 or we can use the dragons! This picture shows how to take away 10 dragons from 30. How many times do we take away 10 from 30 to get to 0?
Click Show Me to see how many times we have to take away 10!
3! We have to take away 10 three times to get to zero.
30 - 10 - 10 - 10 = 0
30 - 10 - 10 - 10 = 0
30 \({ \div }\) 10 = ___
Quotient: The answer to a division problem. The number of items in each group.
The quotient is the number of times we took away 10. We took away 10 three times! We can check our answer by subtracting 10 three times from 30. 30 minus 10 equals 20. 20 minus 10 equals 10. 10 minus 10 equals 0.
Question:
What is 30 \({ \div }\) 10?
30 \({ \div }\) 10 = 3
3 is the quotient. 3 dragons need to go on each quest!
Repeated subtraction helps us divide. We found out that 30 \({ \div }\) 10 = 3 by subtracting three 10s. There are 3 dragons on each quest!