Multiplying Decimals by 10, 100, and 100
0.365 x 100
36.5
Use Hundredths Grid
3.3 x 3
9.9
6.22 x 3
18.66
Double Points (200 Points)
1.2 x 3.6
4.32
Triple Points (300 points)
The wings of a hummingbird beat an average of 52 times per second. If it hovers for 35.5 seconds, on average how many times does its wings beat?
1846 times
0.001 x 10
0.01
Double Points (400 points)
Use Hundredths Grid
4 x 0.46
1.84
Double Points (400 Points)
12 x 4.8
57.6
Estimate:
19.86 x 0.48
Erin wants to buy 11 bars of soap. One bar of soap costs $1.60. How much will the 11 bars cost?
$17.60
7.25 x 1000
7250
Use the grid
0.5 x 0.2
0.1
11 x 3.23
35.53
8.6 x 0.08
0.688
The airline that Mrs. Hamilton is using has a baggage weight limit. He has 5 bags weighing 18.4 pounds each. What is the combined weight of her baggage?
92
0.004 x 10^3
4
Double Points (800 Points)
Use the gird
0.4 x 0.1
0.04
405 x 0.47
190.35
18.1 x 3.7
66.97
Double Points (800 Points)
Milani wrote 23.4 for the product of 7.8 x 0.3
Use number sense to decide if Milani placed the decimal point in the correct place in the product. Explain.
She did not. When we multiply by less than one the product will be less than the bigger factor.
6.02 x 10^2
602.0
Use Hundredths Grid
4 x 0.6
2.4
Estimate and Solve
309 x 4.8
Estimate - 1500
Product- 1,483.2
3.2 x 2.8
8.96
Keaton buys 3.2 pounds of potatoes for $0.70 a pound. He gives the clerk a five dollar bill. How much change will Keaton get back?
$2.76