Answer:
The 90% confidence interval for the mean score of all takers of this test is between 59.92 and 64.08. The lower end is 59.92, and the upper end is 64.08.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 62 - 2.08 = 59.92
The upper end of the interval is the sample mean added to M. So it is 62 + 2.08 = 64.08.
The 90% confidence interval for the mean score of all takers of this test is between 59.92 and 64.08. The lower end is 59.92, and the upper end is 64.08.
Answer:
16 cm2
Step-by-step explanation:
By equa tion of area of triangle: S = 1/2 * height * base
Triangle B: 32 = 1/2 * 8 * x --> x = 8 (cm)
The base of triangle A is half of the base of triangle B so it is 4 cm.
The area of triangle A = 1/2 * 8 * 4 = 16 (cm2)
Answer:
24
Step-by-step explanation:
the area of white board = (2×12) ×4 = 96 sq in.
the area of post-it = 2×2 = 4 sq in
so, numbers of post-it = 96/4 = 24
Answer:
Step-by-step explanation:
The temperature starts at 50 and increases because the slope is positive.
Answer:
35°
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
subtract the sum of the 2 given angles from 180° for missing angle
missing angle = 180° - (90 + 55)° = 180° - 145° = 35°