Dividing by Powers of 10
When dividing 843.23 by 101, how should the decimal point be moved?
To the left, one time.
Alex is dividing 58 ounces of carrots equally into 8 bags. Which is the best way to estimate the amount of cereal in each bag.
A. 60 ÷ 10 = 6
B. 56 ÷ 8 = 7
C. 50 ÷ 5 = 10
D. 54 ÷ 9 = 6
B
Find 5.84 ÷ 4
1.46
Find 94.5 ÷ 15.
6.3
Find 6.4 ÷ 3.2.
2
Use the equation 4.5 ÷ n = 0.45. What value of n makes the equation true? Write your answer using an exponent. Explain how you know your answer is correct.
101
What is a good estimate for 142.9 ÷ 11.9? Write an equation to show your work.
144 ÷ 12 = 12
A box of oil paints contains 9 cans of different colors. Each can is the same weight. If the box weighs 20.25 pounds, how much does each can weigh?
2.25 pounds
June says that there should be a decimal point in the quotient below after the 4? Is she correct? Use number sense to explain your answer.
43.94 ÷ 5.2 = 845
June is not correct. I used compatible numbers to estimate 40 ÷ 5 = 8 and 84.5 is not close to 8. The decimal point belongs after the 8.
How many quarters are in $30? Solve the equation:
30 ÷ 0.25 to help you.
120 Quarters
Mark bought 10 books from the bookstore and paid a total of $14.40. Write an equation to show your work. Explain how the decimal point moves.
9.90 ÷ 10 = 0.99. The decimal point moves to the left one time.
Piper bought 9 roses for 45.50. Which is the best way to estimate the cost of one rose?
A. $45 ÷ 5 = $9.00
B. $48 ÷ 8 = $6.00
C. $45 ÷ 10 = $0.45
D. $40 ÷ 8 = $5.00
A
Michelle pays $66.85 for a costume pattern and 8 yards of fabric. The costume pattern costs $4.85. How much does each yard of the fabric cost?
$7.75
A 12-ounce bottle of shampoo costs $4.20. A 16-ounce bottle costs $6.88. Which shampoo costs less per ounce? How do you know?
The 12-ounce bottle costs less per ounce because it costs $4.20 ÷ 12 = $0.35 per ounce. The 16-ounce bottle costs $6.88 ÷ 16 = $0.43 per ounce.
Find 81.4 ÷ 7.4.
11
What is the value of the missing exponent in the equation 720 ÷ 10? = 0.720
3
Rachel bought 15 pencils for $4.20. Each eraser costs the same amount. Estimate the amount Ken paid for each eraser. Write an equation to model your work.
420 ÷ 20 = 21
Over the course of 5 days, Kiera ran 18.6 miles. She ran the same distance each day. How far did Kiera run each day? Write an equation to show your work.
3.72 miles
A bathroom is rectangular with an area of 44.52 square feet. If the bathroom is 13 feet wide, how long is it?
12.1 feet
One serving of Patrick's soup is 0.75 cup. How many servings are in a 72-cup pot? Evaluate the expression 72 ÷0.75 to help you.
96 servings.
Select all of the following equations that are true when 35.3 is used. Use number sense to help.
1. __ ÷ 10 = 3.53
2. __ ÷ 1 = 353
3. __ ÷ 102 = 0.353
4. __ ÷ 100= 35.3
5. __ ÷ 103 = 0.353
1, 3, 4
Mia's faucet dripped a total of 1.92 liters of water in 24 hours. The faucet dripped the same amount each hour. Estimate how many liters his faucet dripped each hour. Write an equation to model your work.
2 ÷ 20 = 0.1
A family is fencing off a square portion of the backyard for a pool. The perimeter of the square is 48.4 meters. How many meters long is each side of the square? Write an equation to model your work.
48.4 ÷ 4 = 12.1
A baseball team has spent $216 on 15 new baseballs. Each ball costs the same. Find the exact cost of each soccer ball.
14.4
Find 9.6 ÷ 0.03
320