Transcript Lesson X Step X of XX - MathLine Concept

Long Division
Long Division
&
MathLine
First Problem:
____
6)192
Long Division
For traditional Long Division,
teach the algorithm:
1) Divide or D
2) Multiply or M
3) Subtract or S
4) Check or
5) Bring Down or BD
Long Division
1)
2)
3)
4)
5)
Take the problem
____
6)192
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
6 into 1?
____
6)192
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
1)
2)
3)
4)
5)
Put 1 on MathLine
____
6)192
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
6 into 1? No
____
6)192
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
6 into 19?
____
6)192
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
1)
2)
3)
4)
5)
Put 19 on MathLine
____
6)192
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
For long division on MathLine
ALWAYS
start dividing from the left
Long Division
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Yes, how
many
6 into
19?times?
____
6)192
123456
1
One Group of 6
Long Division
____
6)192
1)
2)
3)
4)
5)
Two Groups of 6
123456
1
2
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
1)
2)
3)
4)
5)
Three Groups of 6
____
6)192
123456
1
2
3
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Put a 3 above the 19 of 192
3
____
6)192
Long Division
1)
2)
3)
4)
5)
Now multiply 3 X 6
3
____
6)192
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Make sure
Only
multiplydo
3X
6,
the
students
not
or 3 groups
of 6
multiply
the remainder
back in!
Long Division
3
____
6)192
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Multiply 3 x 6
3 Groups of 6
Long Division
3
____
6)192
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Multiply 3 x 6
3 Groups of 6
Long Division
3
_ ___
6)192
18
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
We multiply 3 x 6
and get 18,
so we put
the 18 below 19
Long Division
3
_ ___
6)192
-18
1
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Subtract 18 from 19,
to get a difference of 1
Long Division
3
_ ___
6)192
-18
1
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Remainder of 1, ‘s
out on MathLine
Long Division
3
_ ___
2
6)192
-18
1
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Bring down
the 2
to get 12
Long Division
Put 12 on MathLine
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
_ 3_
6)192
-18
12
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Does
How many
6 go
Yes
into
times?
12?
Long Division
_ 3_
6)192
-18
12
123456
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
One group of 6
Long Division
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
_ 3_
6)192 Two groups of 6
-18
121 2 3 4 5 6
Long Division
_ 32_
6)192
-18
12
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Put a 2 above
the 2 of 192
Long Division
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
_ 32_
6)192 Now multiply 2 x 6
-18
12
1)
2)
3)
4)
5)
Long Division
2 x 6 = 12
2 Groups of 6
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Long Division
__32
6) 192
-18
12
12
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Put 12 below the 12
Long Division
__32
6) 192
-18
12
-12
0
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Subtract 12 from 12
Long Division
__32
6) 192
-18
12
-12
0
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Remainder of 0,
‘s out on MathLine
Long Division
1)
2)
3)
4)
5)
Divide = D
Multiply = M
Subtract = S
Check =
Bring Down = BD
Recap for Long Division
• MathLine
makes the algorithm concrete,
steps are organized
• Multiplication problem is set up
• Check step is built in
• Makes long division FUN for students