Download - Work It Out
You are asked to solve a few problems and determine a trick that can be used to divide a
decimal by a decimal. By solving these problems with a calculator you quickly see a
pattern to make an easy way to always divide. Explain that pattern and the new “trick” your
peers can use for it. 1)
2)
Work It Out
.05 .75
5. 75.
Ideas?
When the divisor is a
decimal, move the decimal point to the right in the
divisor until it becomes a whole number.
574.25. 574..25
574..25
The number of places you moved the decimal in the divisor, move the decimal
the same number of places in the dividend.
5.74.25
After moving the decimals in both the divisor and dividend, this is your new division problem.
5.74.25574.25.
Now let’s divide. Bring the decimal straight up into the
quotient.
5.74.25 .
Then divide.
5.74.25 1.
25
Subtract and bring down the next
number.
5.74.25 1.
25 225
Finish dividing the problem.
5.74.25 1.9
25 225 225 0
Why does this work?
Quick!
Let’s try another
example.
441.2.1
Move the decimal point to the right in the divisor until it becomes a whole number.
441.2.1
441..12
Move the decimal the same number of places in the dividend.
441..12
44.1.12
After moving the decimals in both the divisor and dividend, this is
your new division problem.
44.1.12144.2.1
.
Bring the decimal point straight up into the quotient.
44.1.12
.1
1 2
Let’s divide!
44.1.12
.1
1 2 24
Subtract and bring down.
44.1.12
.1 2
1 2 24 24
0
Finish dividing.
44.1.12
1)
2)
3)
4)
Now let’s try some on your own!
474.6
5.895
21.922.3
8912.95.
1) .0792) 19.73) 9.14) .22
Answers
Work it out in a race!!!
Let’s split!
Agendas: PB pg 21# 1-9 Choose 4, # 10 and
11
After a while crocodile