Answer:
The z-score when x=187 is 2.41. The mean is 187. This z-score tells you that x = 187 is 2.41 standard deviations above the mean.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question:
The z-score when x=187 is ...
The z-score when x=187 is 2.41. The mean is 187. This z-score tells you that x = 187 is 2.41 standard deviations above the mean.
20m measurement that’s what is equal to 10
Answer:
We conclude that the Pennsylvania school district have an IQ higher than the average of 101.5
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 101.5
Sample mean, 
= 106.4
Sample size, n = 30
Alpha, α = 0.05
Population standard deviation, σ = 15
First, we design the null and the alternate hypothesis
We use one-tailed z test to perform this hypothesis.
Formula:
Putting all the values, we have
Now, 
Since,
We reject the null hypothesis and accept the alternate hypothesis.
Thus, we conclude that the Pennsylvania school district have an IQ higher than the average of 101.5
Answer:
- <u><em>option C) 1.61</em></u>
Step-by-step explanation:
The question is to evaluate the natural logarithm of 5. Natural logarithms are logarithms with base <em>e</em>.
<em>e</em> is the irrational number equal to 2.71828182845904523536028747 ... (being irrational the decimals do not end and do not have a repetition period).
Logarithms are evaluated using tables or scientific calculators.
ln (5) = 1.6094379... it is also an irrational number, so it has infinite decimals with no repetition period.
So, rounding to two decimal numbers, ln (5) = 1.61, which is the option C).
Answer:
1,3 and 5
Step-by-step explanation:
1) -2(7x + 1) − 5(3x2 + 3x + 2)
= -14x - 2 - 15x^2 - 15x - 10
= -15x^2 - 29x - 12
2) (5x2 − 10x + 8) − (10x2 + 19x + 20)
= 5x^2 - 10x + 8 - 10x^2 - 19x - 20
= -5x^2 -29x - 12
3) (-7x2 − 21x + 13) − (8x2 + 8x + 25)
= -7x^2 - 21x + 13 - 8x^2 - 8x - 25
= -15x^2 - 29x - 12
4) (-19x2 − 4x - 7) + (4x2 + 25x − 5)
= -15x^2 + 21x - 12
5) (-17x2 + 2x − 3) + (2x2 − 31x − 9)
= -15x^2 -29x - 12
6) -2(4x − 15) − 3(5x2 + 7x + 6)
= -8x + 30 - 15x^2 - 21x - 18
= -15x^2 - 29x + 12
