Jim's music library on his phone holds 1,900 songs. The songs have an average time of 3.5 minutes. Use scientific notation to find the total number of seconds the playlist will play. Express the answer to the exact decimal place. (1 point)
• 3.99 x 10^5 seconds
• 3.99 x 10^3 seconds
• 0.399 × 10^6 seconds
• 3.99 × 10^4 seconds
To find the total number of seconds the playlist will play, we need to multiply the number of songs by the average time of each song.
Total number of seconds = 1,900 songs * 3.5 minutes/song * 60 seconds/minute
Calculating this, we get:
Total number of seconds = 3.99 × 10^4 seconds
Therefore, the answer is 3.99 × 10^4 seconds.
In chemistry class, Carlos calculated the number of molecules in 100 moles. The calculator displayed the number 6.02E25.
What is the number of molecules in 100 moles in scientific notation? (1 point)
• 6.02 + 10^25
• 6.02 × 25
• 6.02 × 10^25
• 25 x 10^6.02
The number of molecules in 100 moles is given as 6.02E25. This is already in scientific notation, where E represents "times 10 to the power of."
Therefore, the number of molecules in 100 moles in scientific notation is 6.02 × 10^25.
In government class, Nadia computed the amount of debt of the federal government after a third of it was paid in 1995.
The calculator displayed the number 3.28E12. What is this number in scientific notation? (1 point)
• 3.28 × 10^12
• 12 × 10^3.28
• 3.28 x 10^-12
• 3.28 + 10^12
The number 3.28E12 is already in scientific notation, where E represents "times 10 to the power of."
Therefore, the number in scientific notation is 3.28 × 10^12.
Sam is comparing the half-life of two isotopes of uranium. The half-life of Uranium-238 is 4.5 x 10^9 years. The half-life of Uranium-233 is 1.6 x 10^5 years. He computed how much greater the half-life of Uranium-238 is than that of Uranium-233, and his calculator displayed the number 2.81E4. What is this number in scientific notation? (1 point)
• 2.81 x 10^4
• 2.81 × 10^-4
• 2.81 + 10^4
• 4 x 10^2.81
The number 2.81E4 is already in scientific notation, where E represents "times 10 to the power of."
Therefore, the number in scientific notation is 2.81 × 10^4.
Kendra finds the dimensions of a sticky note. She uses a meter stick to determine that the dimensions are 1.25 x 10^-8 meters wide by 2.5 x 10^-6 meters long. Use scientific notation to write the dimensions in millimeters.
Note: 1 meter is equal to 1,000 millimeters.
(1 point)
• 1.25 x 10^-5 by 2.5 x 10^-3 millimeters
• 1.25 × 10^-6 by 2.5 × 10^-4 millimeters
• 1.25 × 10^-11 by 2.5 x 10^-9 millimeters
• 1.25 × 10^-10 by 2.5 × 10^-8 millimeters
To convert the dimensions from meters to millimeters, we need to multiply each dimension by 1,000 since there are 1,000 millimeters in 1 meter.
1.25 x 10^-8 meters * 1,000 = 1.25 x 10^-8 * 10^3 = 1.25 x 10^-5 millimeters
2.5 x 10^-6 meters * 1,000 = 2.5 x 10^-6 * 10^3 = 2.5 x 10^-3 millimeters
Therefore, the dimensions in millimeters are 1.25 x 10^-5 by 2.5 x 10^-3 millimeters.
To find the total number of seconds the playlist will play, we need to multiply the total number of songs by the average time of each song.
The total number of songs is given as 1,900, and the average time of each song is 3.5 minutes. Since there are 60 seconds in a minute, we can convert the average time to seconds by multiplying it by 60:
3.5 minutes * 60 seconds/minute = 210 seconds
Now, we can calculate the total number of seconds the playlist will play by multiplying the total number of songs by the average time:
1,900 songs * 210 seconds/song = 399,000 seconds
Expressing this in scientific notation, we have 3.99 x 10^5 seconds.
Therefore, the answer is 3.99 x 10^5 seconds.