Estimating Decimals
Round to the nearest whole
5.63 + 2.58
6 + 3 = 9
5.45 x 1000
5450
3.56 / 100
.0356
You buy six bags of chips for 2.95 each. Estimate the number of five dollar bills needed.
6 x 3 = 18
I need 4 five dollar bills.
Using a place value chart show
16 / 4
Must have a chart 16 / 4 = 4
four dots in each ones group
Round to the ones
8.25 - 6.99
8 - 7 =1
4.4 x 400
(4. 4 x 4) x 100
17.6 x 100
1760
.27 / 9
0.03
Jane bought 2 pounds of grapes for $2.49 per pound and 3 muffins for $0.75 per muffin. How much did she pay for the grapes and muffins?
2.49 x 2 = 4.98
0.75 x 3 = 2.25
4.98 + 2.25 = 7.23
Must use a place value chart
0.9 / 3
Must show on a chart 0.9 / 3 = 0.3
three dots in each tenths group
Round to the nearest whole
12.23 x 2.84
12 x 3 = 36
.15 x 9
1.35
224 / 200
(224 / 2) / 100
112 / 100
1.12
A bag of flour weighs 15 pounds. A shopkeeper has one bag of flour. She sells 1.065 pounds a day for 8 days. How much is left after eight days?
1.065 x 8 = 8.520
15.00 - 8.52 = 6.48
Using a place value chart
16.05 / 5
Need a place value chart
* each group should have:
- 3 ones
- 2 tenths
- 1 hundredth
Round to the Ones place value
23.63 / 4.19
24 / 4 = 6
63.1 x 60
(63.1 x 6) x 10
378.6 x 10
3786
3.25 / 25
0.13
A piece of rope is 488 meters long. It is cut into 80 pieces. How long is each piece?
(488/ 8) / 10
61 / 10
6.1
Using a number line draw
.6 x 2
Must have a number line
dot one at 0.6
dot two at 1.2
Round to the nearest whole number
1625.33 - 235.1
1625 - 235 = 1390
5.23 x 7000
(5.23 x 7) x 1000
36.61 x 1000
36610
61.59 / 3
20.53
A stack of 4 identical books is 6.28 inches high. What is the height of 30 of these books
Find the height of one book then multiply it by 30
6.28 / 4 = 1.57
1.57 x 30 = 47.1 inches
Use a number line
1.2 x 3
Must have a number line 1.2 x 3
dot one at 1.2
dot two at 2.4
dot three at 3.6