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Decimal Division
Types of Decimal Division
1) Traditional2) Partial Quotients3) Fractional Notation
Example 1: Traditional
• 2.07 ÷ 0.003
• The first decimal goes “in the house” (Dividend is the Den)
• The second decimal goes in front of the house
2.070.003
Example 1: Traditional
Move the decimal point of each decimal until the divisor is a whole number, adding zeros to dividend if necessary
Estimate 2100 ÷ 3 = 700 Since all decimal points are at the end of the numbers,
divide normally – see next slide
2.070.003
2.07 3 00.00 ..
Example 1: Traditional/Partial Quotients
2070 3 2070 36
-18 27
9
-27 00
0
00 0
600-1800 270-270 0
90____ 690
Both methods show an answer close to our estimate of 700
Example 2: Traditional & Partial Quotients
Let’s try an example where a decimal point remains in the dividend (Den)
• 2.07 ÷ 0.3
• More decimal in divisor and dividend over 1 place.
• Estimate: 21 ÷ 3 = 7
2.07 0.3
20.7 3
Example 2: Traditional
20.7 3. 1. Put decimal point
directly above theone in the Den.
2.Does 3 go into 2? No.
3.Does 3 go into 20?Yes.
0
-18 2
6
7
4.Does 3 go into 27?Yes.
-27 0
9
6.9 is close to our estimate of 7
Example 2: Partial Quotients
20.7 31. Forget about decimal until the end.
3. Divide with benchmarks 3 x 50 = 150
5 0
3 x 10 = 30
-150 57 1 0
-30 27
3 x 9 = 27 9
-27 0
6 9
4. Since our estimate was 7, place decimal point between the 6 and the 9
Answer: 6.9
2. Estimate: 21 ÷ 3 = 7
Example:
• Let’s try: 0.125 ÷ 0.05
• Move decimal point so that the divisor (0.05) is a whole number
• Estimate: 10 ÷ 5 = 2
• Try your method
5 12.5
– What to do if there is a number leftover?
6.7 ÷ 0.21. Start the same…house/move decimal
points/make estimate
6.7 0.2
67 2 Estimate: 70/2 = 35
67 2 67 2
-6
-6 0
3
7
3
10
5
-10 0
03 0
-60 7 3
-6 1
0
0 5
-10 0
3 3 5
Estimate: 35Where does the decimal go?
