Answer:
The solution is (2,6)
Step-by-step explanation:
Let
x-----> the number of hours to change a fuel injection unit
y-----> the number of hours to change a transmission
we know that
5x+10y=70 -----> equation A
8x+8y=64 -----> equation B
Solve the system of equations by graphing
Remember that the solution of the system of equations is the intersection point both graphs
The solution is the point (2,6)
see the attached figure
Answer:
a. If a sample of size 200 is taken, the probability that the proportion of successes in the sample will be between 0.47 and 0.51 is 41.26%.
b. If a sample of size 100 is taken, the probability that the proportion of successes in the sample will be between 0.47 and 0.51 is 30.5%.
Step-by-step explanation:
This problem should be solved with a binomial distribution sample, but as the size of the sample is large, it can be approximated to a normal distribution.
The parameters for the normal distribution will be
We can calculate the z values for x1=0.47 and x2=0.51:
We can now calculate the probabilities:
If a sample of size 200 is taken, the probability that the proportion of successes in the sample will be between 0.47 and 0.51 is 41.26%.
b) If the sample size change, the standard deviation of the normal distribution changes:
We can calculate the z values for x1=0.47 and x2=0.51:
We can now calculate the probabilities:
If a sample of size 100 is taken, the probability that the proportion of successes in the sample will be between 0.47 and 0.51 is 30.5%.