This document provides instructions for dividing multi-digit numbers by one-digit divisors using the "family method". It explains the parts of a division problem and the steps to solve it. The family method involves finding the closest multiple (Father), multiplying it by the divisor (Mother), subtracting (Sister), and bringing down the next digit (Brother). Examples are provided to demonstrate solving a full division problem using this step-by-step method. Students are assigned practice problems to reinforce the technique.

1. DivisionDivision
by Oneby One
DigitDigit
DivisorsDivisorsAllegra JamesAllegra James
and Larry Wershbaleand Larry Wershbale
Media Design and ProductionMedia Design and Production
ISTC 665ISTC 665

2. • Dividing these 16 apples
into 4 equal groups,
gives you 4 groups that
have 4 apples in each of
the groups:
       
       
What are you doing whenWhat are you doing when
you divide?you divide?
• When you divide, you
are trying to split
something into equally
numbered groups
• Take these 16 apples:
       
       

3. Division by One-digit DivisorsDivision by One-digit Divisors
• Today you will learn how to divide a
three-digit dividend by a one-digit
divisor, to get a quotient without a
remainder
• Let’s review these terms

4. What are the parts of aWhat are the parts of a
division problem?division problem?
• The dividend is the number you are dividing
• The divisor is the number you are dividing by
• The quotient is the evenly divided result
• The remainder is what is left over that cannot
be evenly divided

5. When we write the problemWhen we write the problem
like this:like this:
136136  5 = 27 r 15 = 27 r 1
136
is the
dividend
5
is the
divisor
27
is the
quotient
1
is the
remainder

6. When writing it like this:When writing it like this:
136, the
dividend,
moves here
5, the
divisor,
moves
to here
27, the
quotient,
stays
here
1 is the
remainder1365
27 r 1

7. How do you solve aHow do you solve a
division problem?division problem?
• Solving a division problem is a step by step
process
• The method we will learn today is based the
words for the people in our families.
• They are:
Father Mother Sister Brother

8. The “Family” MethodThe “Family” Method
Father = Find
Mother = Multiply
Sister = Subtract
Brother = Bring Down

9. FatherFather
• Father stands for find
• Start by looking at the first number in the dividend
• Find the multiple of the divisor that comes closest
to that number, without going higher
• Use your knowledge of math facts, or a
multiplication grid

10. 7113
FFather =ather = findfind the number closet to the first digitthe number closet to the first digit
• In the 3’s, the number
closest to 7, but not
more than 7, is 6
• The other factor is 2
6
• Put a 2 above the 7
2
2

11. MMother =other = multiplymultiply the number that is thethe number that is the
factor that you found times the divisorfactor that you found times the divisor
• You found 2, multiply
it times the divisor, 3
• 2 times 3 equals 6
2 X 3 = 6
• Put a 6 under the 7
7113
2
6

12. SSister =ister = subtractsubtract the number you got bythe number you got by
multiplying the divisor,multiplying the divisor,
from the number in the dividendfrom the number in the dividend
• You got a 6 when you multiplied
• Subtract 6 from 7
7113
2
6
• 7 – 6 = 1
–
1
• The difference must be smaller than the divisor!!!The difference must be smaller than the divisor!!!

13. BBrother =rother = bring downbring down the next number,the next number,
from the number in the dividendfrom the number in the dividend
• Bring down the next number in
the dividend
• The new number you have is 11
• Now start over again with Father for the ten’s
7113
2
6–
11
1

14. Now, let’s do the second stepNow, let’s do the second step
• Father: 9 is the closest multiple,
the other factor you found is 3
• Mother: 3 X 3 = 9, put a 9 under
the 11
• Sister: subtract 9 from 11
11- 9 = 2
7113
2
6–
11
1
• Brother: bring down the 1
3
9–
21

15. Now, let’s do the last stepNow, let’s do the last step
• Father: 21 is the closest multiple,
the other factor is 7
• Mother: 7 X 3 = 21, put 21 under
the 21
• Sister: subtract 21 from 21
21- 21 = 0
• Brother: nothing’s left, you’re done!
7113
2
6–
11
1
3
9–
21
21–
0
7

16. 8644
2
8–
6
6
Now, let’s practice!Now, let’s practice!
• Father
• Mother
• Sister
• Brother
0
2
4 8

17. Now, let’s do the second stepNow, let’s do the second step
• Father
• Mother
• Sister
8644
2
8–
06
6
• Brother
1
4–
24
4

18. Now, let’s do the last stepNow, let’s do the last step
• Father
• Mother
• Sister
• Brother
8644
2
8–
06
6
1
4–
24
24–
0
6

19. • Finish the rest of the worksheet
• Homework: probs. 1-10, p. 64 in text
• Go to this icon on the class’
computers for extra practice if you have
free time
• Look for the same icon on the class’
website for practice at home
What do I do with division now?What do I do with division now?