Answer:
40
Step-by-step explanation:
Let the number be y
-1/2 × y = -20
y = -20 ÷ -1/2
y = 20 × 2
y = 40
Answer:
C. Decreases the margin of error and hence increases the precision
Step-by-step explanation:
If we select a sample by Simple Random Sampling in a population of “infinite” size (a population so large that we do not know its size exactly), then the margin of error is given by
where
<em>Z = The Z-score corresponding to the confidence level
</em>
<em>S = The estimated standard deviation of the population
</em>
<em>n = the size of the sample.
</em>
As we can see, since n is in the denominator of the fraction and the numerator is kept constant, the larger the sample size the smaller the margin of error, so the correct choice is:
C. Decreases the margin of error and hence increases the precision
Step-by-step explanation:
Mean = 81740
Standard deviation = 4590
Sample size = 15
Alpha level = 1-0.95 = 0.05
Df = 15-1 = 14
Critical value:
alpha/2 = 0.05/2 = 0.05
t0.025
t critical value = 2.145
Margin of error ME
2.145 x 4590/√15
2.145 x 4590/3.873
ME = 2542.09
Confidence interval
Lower CI = mean - ME
= 81740-2542.09
= 79197.91
Upper CI = mean + ME
= 81740+2542.09
= 84282.09
[ 79197.91, 84282.09]
B.
Using excel, exact answer for CI
Lower limit = 79198.142724212173
Upper limit = 84281.8572757827
C.
The assumptions to be made from the population are that
1. Samples are random
2. These samples are gotten from an approximately normal distribution
Answer: 4.8
Step-by-step explanation:
Corresponding sides of similar figures are proportional, so

Answer: Yes, the highest side would be F