Answer:
1) Reject null hypothesis if t > 3.143
2) t = 2.008
Step-by-step explanation:
We are given the following in the question:
Sample size, n = 8
Correlation, r = 0.634
Significance level = 0.01
First we design the null and the alternate hypothesis:
This is a one tailed test.
1) Decision rule
Degree of freedom = n - 2 = 6
So if the calculated test statistic is greater than 3.143, we fail to accept the null hypothesis and reject it.
2) Test statistic
Answer:
5/7
Step-by-step explanation:
Let the numerator = x
Denominator = x + 2
Cross multiply,
2*x = 1(x +5)
2x = x+5
Subtract 'x' from both sides
2x - x = 5
x = 5
The numerator = x = 5
Denominator = x + 2 = 5+2 = 7
Answer:
0.3520
Step-by-step explanation:
We have been given that the pulse rates among healthy adults are normally distributed with a mean of 80 beats/second and a standard deviation of 8 beats/second. We are asked to find the proportion of healthy adults have pulse rates that are more than 83 beats/sec.
First of all, we will find z-score corresponding to sample score of 83 as:
, where,
z = Z-score,
x = Sample score,
= Mean,
= Standard deviation.
Upon substituting our given values in z-score formula, we will get:
Now, we need to find the probability that a z-score is greater than 0.38.
Using formula , we will get:
Using normal distribution table, we will get:
Therefore, 0.3520 of healthy adults have pulse rates that are more than 83 beats/sec.