Which number is correctly written in scientific notation?(1 point)

Question

Responses

2.520 × 10^3
2.520 × 10^3

10 × 10^3
10 × 10^3

0.2520 × 10^−3
0.2520 × 10^−3

25.20 × 10^3
25.20 × 10^3
Question 2
The age of Earth is about 4.6 × 10^9
years old. What is the number in decimal notation?(1 point)
Responses

46,000,000,000
46,000,000,000

4,600,000,000
4,600,000,000

0.0000000046
0.0000000046

4.6000000000
4.6000000000
Question 3
Use scientific notation to compare the following numbers. Which number has the greatest value?

3,478,660

34,870,000

34,786,600



(1 point)
Responses

3.47866 × 10^7
3.47866 × 10^7

3.47866 × 10^6
3.47866 × 10^6

34,870,000
34 comma 870 comma 000

3.487 × 10^7
3.487 × 10^7
Question 4
The density of oxygen is about 1.429 × 10^−4
grams per liter. Which number is higher than that?(1 point)
Responses

4.129 × 10^−4
4.129 × 10^−4

1.429 × 10^−3
1.429 × 10^−3

1.429 × 10^−5
1.429 × 10^−5

1.429 × 10^−6
1.429 × 10^−6
Question 5
Linda converted 0.0005 liters to milliliters using a calculator. The calculator displayed the number 5E−7
. What is this number in scientific notation?(1 point)
Responses

−7 × 10^5
−7 × 10^5

5 × 10^−7
5 × 10^−7

5 + 10^−7
5 + 10^−7

5 × 10^7
5 × 10^7
Question 6
Which expression is equal to 5.1 × 10^−3
?(1 point)
Responses

3.9 × 10^−3 + 1.2 × 10^−3

2.9 × 10^−3 + 1.2 × 10^−3
2.9 × 10^−3 + 1.2 × 10^−3

3.5 × 10^3 + 1.6 × 10^−6
3.5 × 10^3 + 1.6 × 10^−6

2.2 × 10^−1 + 2.9 × 10^−2
2.2 × 10^−1 + 2.9 × 10^−2
Question 7
In 1500CE, the world's population was about 4.5 × 10^8
. In 2020, the world's population was about 7.8 × 10^9
. How much has the world's population increased?(1 point)
Responses

3.3 × 10^9
3.3 × 10^9

7.35 × 10^9
7.35 × 10^9

12.3 × 10^9
12.3 × 10^9

8.25 × 10^9
8.25 × 10^9
Question 8
In 2010, approximately 4.6 × 10^7
tons of paper were recycled. In the same year, an estimated 2,600,000 tons of plastics were recycled. How many more tons of paper was recycled than plastic?(1 point)
Responses

434 × 10^7
434 × 10^7

4.34 × 10^7
4.34 × 10^7

4.34 × 10^2
4.34 × 10^2

7.20 × 10^7
7.20 × 10^7
Question 9
There are about 6 × 10^19
atoms in a grain of sand. A cubic foot of sand can hold about 4 × 10^9
grains of sand. Using those figures, how many atoms would you expect to find in a cubic foot of sand? (1 point)
Responses

2.4 × 10^28
2.4 × 10^28

2.4 × 10^29
2.4 × 10^29

24 × 10^29
24 × 10^29

24 × 10^28
24 × 10^28
Question 10
A gallon of water weighs about 8.3 lb. An Olympic-sized swimming pool holds 6.6 × 10^5
gallons. What is the approximate weight of the water in an Olympic-sized swimming pool?(1 point)
Responses

5.478 × 10^5 lb
5.478 × 10^5 lb

54.78 × 10^5 lb
54.78 × 10^5 lb

54.78 × 10^6 lb
54.78 × 10^6 lb

5.478 × 10^6 lb
5.478 × 10^6 lb
Question 11
A penny weighs 5.8 × 10^−3
lb. How many pennies are in a pile of pennies that weighs 3.596 × 10^4
lb? (1 point)
Responses

6.2 × 10^−7
6.2 × 10^−7

0.62 × 10^7
0.62 × 10^7

6.2 × 10^8
6.2 × 10^8

6.2 × 10^6
6.2 × 10^6
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Answer 1

Here are the answers to each of the questions:

Question 1: Which number is correctly written in scientific notation?

• Answer: 2.520 × 10^3

Question 2: The age of Earth is about 4.6 × 10^9 years old. What is the number in decimal notation?

• Answer: 4,600,000,000

Question 3: Use scientific notation to compare the following numbers. Which number has the greatest value?

• Answer: 3.487 × 10^7 (since 34,870,000 is equal to 3.487 × 10^7)

Question 4: The density of oxygen is about 1.429 × 10^−4 grams per liter. Which number is higher than that?

• Answer: 1.429 × 10^−3 (this is equivalent to 0.001429, which is higher than 0.0001429 of 1.429 × 10^−4)

Question 5: Linda converted 0.0005 liters to milliliters using a calculator. The calculator displayed the number 5E−7. What is this number in scientific notation?

• Answer: 5 × 10^−7

Question 6: Which expression is equal to 5.1 × 10^−3?

• Answer: 3.9 × 10^−3 + 1.2 × 10^−3 (this equals 5.1 × 10^−3)

Question 7: In 1500CE, the world's population was about 4.5 × 10^8. In 2020, the world's population was about 7.8 × 10^9. How much has the world's population increased?

• Answer: 7.35 × 10^9 (which is 7.8 × 10^9 - 4.5 × 10^8 = 7.35 × 10^9)

Question 8: In 2010, approximately 4.6 × 10^7 tons of paper were recycled. In the same year, an estimated 2,600,000 tons of plastics were recycled. How many more tons of paper was recycled than plastic?

• Answer: 4.34 × 10^7 (since 2,600,000 is 2.6 × 10^6, then the difference is 4.6 × 10^7 - 2.6 × 10^6 = 4.34 × 10^7)

Question 9: There are about 6 × 10^19 atoms in a grain of sand. A cubic foot of sand can hold about 4 × 10^9 grains of sand. Using those figures, how many atoms would you expect to find in a cubic foot of sand?

• Answer: 2.4 × 10^28 (6 × 10^19 atoms per grain × 4 × 10^9 grains = 2.4 × 10^28 atoms)

Question 10: A gallon of water weighs about 8.3 lb. An Olympic-sized swimming pool holds 6.6 × 10^5 gallons. What is the approximate weight of the water in an Olympic-sized swimming pool?

• Answer: 5.478 × 10^6 lb (6.6 × 10^5 gallons × 8.3 lb/gallon = 5.478 × 10^6 lb)

Question 11: A penny weighs 5.8 × 10^−3 lb. How many pennies are in a pile of pennies that weighs 3.596 × 10^4 lb?

• Answer: 6.2 × 10^6 (3.596 × 10^4 lb ÷ 5.8 × 10^−3 lb/penny = 6.2 × 10^6 pennies)

Let me know if you need any further assistance!