Algebra 2

Noise Level: A social scientist found that the percent (P) of people who are “highly annoyed” by noise from household appliances, traffic, airports, and so on depend on the decibel level (L) of the noise. The following function is used to find the noise level: P(L)=0.8553L-0.0401L2 +0.0047L3 A vacuum cleaner makes noise of approximately 80 decibels. Part A: What percent of people are highly annoyed by a noise level of 80 decibels? Part B: What percent of people are highly annoyed by a noise level of 0 decibels? What does this tell you about the graph of this polynomial?

13 thoughts on “Algebra 2

  1. A) 0.553(80)-0.0401(80)^2 +0.0047(80)^3
    44.424-1.0291264+0.0005
    Approximately 43.4%

    B) 0-0+0=0%
    This shows that no one is annoyed by zero decibels of sound, since it can’t be heard. Though, at a noise of 80 decibels, 43.4% of people tend to get annoyed.

  2. A. about 43% of people
    B. 0% of people
    Nobody is annoyed by 0 decibels of noise because that can’t even be heard, but approximately 43% of people are annoyed by 80 decibels of noise.

  3. A. about 43\44%.
    B. 0%
    If you cannot hear anything, like if the decibels are at 0%, how can you be annoyed? The 80 decibels are most likely going to be heard, therefore the noise will be more irritable to more people.

  4. a) about 43%
    b) 0% this implies that 0% of people are annoyed with 0 decibels and 43% are annoyed with 80 decibels of noise.

  5. A)

    L=80 DECIBELS
    P(L)=0.5553L-0.0401L^2+0.0047L^3
    P(80)=0.5553(80)-0.0401(80)^2+0.0047(80)^3
    =44.424 + 10.291264 + 0.05315738
    P=54.7684214 X 80%
    P=43.8%

    B)

    0% of people are annoyed by a noise level of 0 decibels since 0 decibels can’t be heard, however 43.8% of people are highly annoyed by a vacuum cleaner that makes noise of approximately 80 decibels.

  6. A. Approx. 43.4% of people get annoyed.
    B. 0% of people get annoyed by 0 decibels of sound because it can not be heard. Approx. 43.4% of people get annoyed by 80 decibels because they are the only percentage that are able to hear it.

  7. A)
    L=80 decibels
    P(L)=0.5553L-0.0401L^2+0.0047L^3
    P(80)=0.5553(80)-0.0401(80)^2+0.0047(80)^3
    P(80)=44.424-256.64+2406.4
    P(80)=2194.184

    B)
    P(0)=0.5553(0)-0.0401(0)^2+0.0047(0)^3
    P(0)=0
    The polynomial is a cubic function. It starts at 2194.184 and gradually goes down as L gets smaller. When the decibels are set to 0 it does not annoy a person because the average person does not hear noise that low.

  8. A) about 43% of people get annoyed
    B) 0% of people get annoyed by the the 0 decibels because 0 decibels = no sound able to be heard, and no sound being heard can’t be annoying

  9. a) about 43% of people are highly annoyed with a noise that reaches 80 decibles
    b) 0% of the people are irritated by a noise that reaches 0 decibles. this implies that the graph will always stay above the x-axis because every number above zero is positive

  10. I think this is worded incorrectly or there is a mistake in the equation because the way the people who answered it are getting 43% is incorrect for they would have multiplied -0.0401 by 80 before squaring the 80 which to be correct in the equation, would then have to be set up as P(L)=0.5553L-(0.0401L)^2+(0.0047L)^3 instead of the original P(L)=0.5553L-0.0401L^2 +0.0047L^3. For if you work out the problem with the original equation correctly, it would give you 2194 which is not the percentage.

  11. a.) About 43.4% of people are highly annoyed
    b.) 0% of people are highly annoyed because 0 decibels of sound cannot be heard.
    This problem might be a little inaccurate because everyone has abilities to hear different frequencies of sound. You can’t judge the percentage of highly annoyed people with a sound not everyone can hear.

  12. A)
    P(L)=0.5553L-0.0401L^2+0.0047L^3
    P= approx. 2,300

    P(L)= 0.5553L-(0.0401L)^2+(0.0047L)^3
    P= 41.592 so approx. 42% of the people that the scientists researched were ‘highly annoyed’ by the noise.

    B) If there is a case with 0 decibels, then zero people are annoyed by the sound.

    Who did the scientists test to see who ‘annoyed’ by the noise? How many people? The graph, I believe, will be positive negative negative. Any decibel above zero will be positive, maiking the graph an upward graph.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s