Dividing by Powers of 10
98.3 ➗ 10²
.983
Estimate the quotient:
23.90 ➗ 7.9
24 ➗ 8 = 3
21 ➗ 7 = 3
3.25 ➗ 5
0.65
When dividing 702.9 by 100, how should the decimal point be moved?
Two places to the right, making the quotient 7.029.
A tile in one of the classrooms in Jane's school is rectangular, and has an area of 43.96 square centimeters. If the length of the tile is 14 centimeters, what is the width?
3.14 centimeters
568.09 ➗ 10²
5.6809
Estimate the quotient:
57.99 ➗ 6.6
56 ➗ 7 = 8
3 ➗ 6
0.5
Jesse is buying a case of soda. 12 soda cans cost $8.99. How much is one can of soda? (remember to round)
$0.75 per can
A donation box for a food pantry has 8 large cans of corn. Each can is the same weight. If the box weighs 19.36 pounds...
How much does each can of corn weigh?
How much would the box weigh if there were 6 cans of corn?
2.42 pounds for 1 can
14.52 pounds for 6 cans
_____ ➗ 10³ = 76.02
76,020
654.9 ➗ 8.1
640 ➗ 8 = 80
3.6 ➗ 15
(you may need to annex zeros)
0.24
Jamie says that there should be a decimal point in the quotient below after the number 5 in the ones place. Is she correct? Use number sense to explain your answer.
33.075 ➗ 6.3 = 525
Yes. She is correct.
1) If you do long division, you can divide 6 into 33, and place the first digit in the ones place.
2) If you estimate, 30 divided by 6 = 5 OR 36 divided by 6 equals 6, meaning the quotient is in the ones place.
Over the course of 5 days, Emily wrote a term paper. It took her 15.85 hours to write it, and she spent the same amount of time to write it each day. How long did she spend each day writing the paper?
3.17 hours each day
What is the difference between dividing by powers of 10 and multiplying by powers of 10?
When you divide by a power of 10, you move the decimal to the left, and when you multiply. by a power of 10, you move the decimal to the right.
When you divide by a power of 10, the quotient becomes smaller, and when you multiply, the product becomes larger.
489.09 ➗ 72.9
490 ➗ 70 = 7
480 ➗ 80 = 6
91.6 ➗ 8
(you may need to annex zeros)
11.45
3.18 ➗ 0.3
10.6
$22.71
4,907 ➗ 10³
4.907
598.09 ➗ 59.9
600 ➗ 60 = 10
0.132 ➗ 0.02
6.6
Dana divided 2.15 by .05 and got a quotient of 0.43. Did she make a mistake? If so, what was her mistake, and what should the correct answer be?
She made a mistake. Dana forgot to move the decimal point 2 times in the divisor. Her answer should be 43, not 0.43.
Pamela bought 100 stuffed animals from a website, and spent $180. What was the cost of each stuffed animal? Write an equation to model your work.
(remember, we are talking about money, and your answer needs to be in the hundredths place)
$180 ➗ 100 = 1.8 = $1.80