Answer:
b and d/ a and c
Step-by-step explanation:
Answer:
A. 4
Step-by-step explanation:
4*x-4*1=4x-4
Answer:
95% two-sided confidence interval on the true mean breaking strength is (94.8cm, 99.2cm)
Step-by-step explanation:
Our sample size is 11.
The first step to solve this problem is finding our degrees of freedom, that is, the sample size subtracted by 1. So
.
Then, we need to subtract one by the confidence level
and divide by 2. So:

Now, we need our answers from both steps above to find a value T in the t-distribution table. So, with 10 and 0.025 in the two-sided t-distribution table, we have 
Now, we find the standard deviation of the sample. This is the division of the standard deviation by the square root of the sample size. So

Now, we multiply T and s
cm
For the upper end of the interval, we add the sample mean and M. So the upper end of the interval here is
cm
So
95% two-sided confidence interval on the true mean breaking strength is (94.8cm, 99.2cm).
Answer: Approximately 4.7 hours.
Step-by-step explanation:
He rode the bicycle for some time before it broke down and he walked the remaining distance. This means that Jim covered a total of 165 miles by riding at a speed of 35 miles per hour and walking at a speed of 3 miles per hour.
Let x = the distance covered by riding the bicycle.
Let y = the distance covered by walking.
Time = distance /speed
Time he used in riding would be x/35
Time he used in walking would be y/3
Since the entire trip took 7 hours,
x/35 + y/3 = 7
3x + 35y = 735 - - - - - - - - 1
Total miles covered is 165. Therefore,
x + y = 165 - - - - - - - - -- - -2
Substituting x = 165-y into equation 1, it becomes
3(165-y) + 35y = 735
495-3y + 35y = 735
-3y + 135y = 735-495
132y = 240
y = 240/132
y = 1.81m
x = 165 - 1.81 = 163.19
Amount of time that he spent on the bicycle will be
x/35 = 163.19/35
= 4.66
Approximately 4.7 hours.