Convert numbers to scientific notation and vice versa

What is the best way to represent 450,000 in scientific notation?

• 4.5 x 10^4

• 4.5 x 10^5

• 4.5 x 10^6

• 4.5 x 10^3

Answer explanation

To convert 450,000 to scientific notation, move the decimal point to the left until there is only one non-zero digit to the left. This gives 4.5 x 10^5.

What is the magical standard form of 6.75 x 10^4?

• 60075

• 67000

• 67500

• 6750

Answer explanation

To convert 6.75 x 10^4 to standard form, move the decimal point 4 places to the right, resulting in 67500.

Which of the following statements correctly compares the numbers 3.2 x 10^5 and 5.6 x 10^4 in scientific notation?

• 3.2 x 10^5 = 5.6 x 10^4

• 3.2 x 10^5 + 5.6 x 10^4

• 3.2 x 10^5 > 5.6 x 10^4

• 3.2 x 10^5 < 5.6 x 10^4

Answer explanation

3.2 x 10^5 is greater than 5.6 x 10^4 because the exponent in the first number is larger, indicating a larger value.

Which celestial body is closer to Earth, the Sun or the Moon?

• Venus

• Mars

• Mercury

• Sun

Answer explanation

The distance from Earth to the Sun (1.496 x 10^8 km) is greater than the distance from Earth to the Moon (3.844 x 10^5 km), so the correct choice is Sun.

What is the scientific notation for the number 0.0000072?

• 7.2 x 10^7

• 7.2 x 10^-6

• 7.2 x 10^-8

• 7.2 x 10^-7

Answer explanation

To express 0.0000072 in scientific notation, move the decimal point to the right until there is only one non-zero digit to the left. This gives 7.2 x 10^-7.

What is the standard form of 9.2 x 10^-6?

• 0.92 x 10^-5

• 92 x 10^-7

• 9.2 x 10^-6

• 9.2 x 10⁶

Answer explanation

To write 9.2 x 10^-6 in standard form, keep the decimal point after the first digit, resulting in 9.2 x 10^-6.

Which of the following statements correctly compares 2.5 x 10^3 and 4.7 x 10^2 in scientific notation?

• 2.5 x 10^3 is equal to 4.7 x 10^2

• 2.5 x 10^3 is greater than 4.7 x 10^2

• 4.7 x 10^2 is greater than 2.5 x 10^3

• 2.5 x 10^3 is less than 4.7 x 10^2

Answer explanation

2.5 x 10^3 is greater than 4.7 x 10^2 because 2.5 x 10^3 is equivalent to 2500 while 4.7 x 10^2 is equivalent to 470.

Which subatomic particle is the heavyweight champion of the universe?

• proton

• photon

• electron

• neutron

Answer explanation

The proton has a greater mass than the electron. The mass of a proton is approximately 1.67 x 10^-27 kg, while the mass of an electron is approximately 9.11 x 10^-31 kg.

What is the magical standard form of 21,000,000?

• 20000000

• 21000000

• 2100000

• 210000000

Answer explanation

To convert 2.1 x 10^7 to standard form, move the decimal point 7 places to the right, resulting in 21000000.

How would you represent 0.00000045 in a scientific way?

• 4.5 x 10^-6

• 4.5 x 10^-7

• 4.5 x 10^7

• 4.5 x 10^-8

Answer explanation

To convert 0.00000045 to scientific notation, move the decimal point to the right until there is only one non-zero digit to the left. This gives 4.5 x 10^-7.