Answer:
Step-by-step explanation:
Hello!
To study the threshold of hering the researcher took a random sample of 80 male college freshmen.
The students underwent an audiometry test where a tome was played and they had to press a button when they detected it. The researcher recorded the lowest stimulus level at which the tone was detected obtaining a sample mean of X[bar]= 22.2 dB and a standard deviation of S= 2.1 dB
To estimate the population mean, since we don't have information about the variable distribution but the sample size is greater than 30, you can use the approximation of the standard normal distribution:
X[bar] ±
Where the semiamplitude or margin of error of the interval is:
d=
Using a 95% level
d= 1.965 *
d= 0.46
The point estimate of the population mean of the threshold of hearing for male college freshmen is X[bar]= 22.2 db
And the estimation using a 95%CI is [21.74;22.66]
I hope this helps!
The value of n could be 180 or 360 degrees maybe.
Answer:
D. It is not possible to draw a conclusion
Step-by-step explanation:
we are not given enough information about the library schedule.
Answer:
By comparing the ratios of sides in similar triangles ΔABC and ΔADB,we can say that
Step-by-step explanation:
Given that ∠ABC=∠ADC, AD=p and DC=q.
Let us take compare Δ ABC and Δ ADB in the attached file , ∠A is common in both triangles
and given ∠ABC=∠ADB=90°
Hence using AA postulate, ΔABC ≈ ΔADB.
Now we will equate respective side ratios in both triangles.
Since we don't know BD , BC let us take first equality and plugin the variables given in respective sides.
Cross multiply
Hence proved.
Answer:
y +5 = (-2/3)(x -4)
Step-by-step explanation:
The point-slope form of an equation of a line with slope m through point (h, k) is ...
... y -k = m(x -h)
You have (h, k) = (4, -5) and a slope the same as that of the parallel line, m = -2/3. Then the equation is ...
... y -(-5) = (-2/3)(x -4)
... y +5 = (-2/3)(x -4)