Answer: 2.28%
Step-by-step explanation:
Given: An airport find that at the present time, the mean noise level is 103 decibels and the standard deviation is 5.4 decibels.
The distribution of noise levels(x) for all jets during takeoff over the neighborhood has a normal distribution.
The probability that jets have a noise level less than 92.2 decibels when taking off over this neighborhood will be :-
Hence, the percent of these jets have a noise level less than 92.2 decibels when taking off over this neighborhood = 2.28%
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Andre45 [30]
Answer:
the one real zero is in the interval (-1, 0)
Step-by-step explanation:
Descartes' rule of signs tells you there are 0 or 2 positive real zeros. Changing the signs of the odd-degree terms and applying that rule again tells you there is one negative real zero. At the same time, those coefficients (-3, -5, -5, +7) have a negative sum, so you know ...
f(-1) = -6
f(0) = +7
so there is a zero in the interval (-1, 0).
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You can try a few values between x=0 and x=10 to see what the function does in that part of the graph. You find ...
f(1) = 10
f(2) = 21
f(3) = 58
So, it is safe to conclude that there are no real zeros for x > 0.
The only real zero of f(x) is in the interval (-1, 0).
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I like to use a graphing calculator for problems like this.
You have a fifty percent chance of heads or tails, so the probability of it landing on the same side twice is 25 percent.
Answer:
900.
Step-by-step explanation:
The first 6 square numbers are 1, 4, 9, 16, 25, 36,
The required product is 25 * 36
= 900.
Let the two integers be x and x + 1, then
2(x + 1) + 9 = 3x
2x + 2 + 9 = 3x
3x - 2x = 11
x = 11
Therefore, the integers are 11 and 12.
