Operations & Place Value
Multiply: What is 5.3×0.1?
0.53
Power pattern: When multiplying a decimal by 10, where does the decimal point move?
One place to the right.
Janice measured a garden length 12 ft and width 4.5 ft. What is the area in square feet?
54.0 ft squared
Amanda took $28.57 to the store and bought two packages at $7.86 each. How much money is left?
$12.85
Estimate: 7.2×0.5
Estimated answer: 3.6 (because 7.2×0.5≈3.6)
What is 7.8×0.01?
Answer:0.078
What is the product of 8.5×0.1?
0.85
Find the area of a rectangle with sides 0.6m and
0.9m (write the area in square meters).
0.54 square meters
Brayan bought 4 large boxes for $7.68 each and 5 small boxes for $3.69 each. How much did Brayan spend in all?
$49.17
Estimate: 4.9×0.2
1.0
How many times greater is 6.7×10 than 6.7×0.1?
100 times greater
Explain why multiplying by 0.01 is the same as moving the decimal point two places to the right.
Multiplying by 0.01 equals dividing by 100, so the decimal moves two places right.
What is the area of a square with side length 3.6 cm?
12.96 square cm
Janice measured her mother's garden: length 12 ft and width 4.5 ft. What is the area of the garden in square feet?
54 square feet
Estimate: 3.3×0.93
3.3
What is 0.54×1 (write the product and explain place value shifting)?
There is NO SHIFT when multiplying by one.
What is 12.85 x 0.1 and what is 12.85 x 10? Compare the difference between the products.
128.5 is 100 times greater than 1.285.
What is the area of a rectangle with length 5 m and width 0.4 m?
2.0 square meters
A gardener bought 3 bags of soil. Each bag costs $4.75. How much did the gardener spend in total?
$14.25
Estimate: 12×0.5
6
Kevin bought 4 large boxes for $7.68 each and 5 small boxes for $3.69 each. What is the total cost?
$49.17
Find my error:
129.6 is 10 times greater than 12.96.
Correct answer: 129.6 is ten times greater than 12.96
A square has side length 2.5 cm. What is its area?
6.25 square cm
A rectangular planter is 1.2 m long and 0.8 m wide. What is the area of the planter in square meters?
0.96 square meters
Estimate: 6.8×0.36
2.1 or less