(c) The number of cars found to have unsafe tires among the 379 cars stopped at a roadblock for inspection (assume that 15% of all cars have one or more unsafe tires).
(i) Find the mean. (Give your answer correct to one decimal place.)
56.85.
(ii) Find the standard deviation. (Give your answer correct to two decimal places.) 6.79
.
(d) The number of melon seeds that germinate when a package of 60 seeds is planted (the package states that the probability of germination is 0.89.
(i) Find the mean. (Give your answer correct to one decimal place.)
Correct: 53.40.
(ii) Find the standard deviation. (Give your answer correct to two decimal places.)
3.10
I got this one finally worked out right, but thanks anyway
Sorry clicked on wrong problem, this guy may need help on this one.
We know that Nora and Tommy are the same person.
Please use only one name for your posts.
No they are not the same person, we are using the same computer....
To find the mean and standard deviation, we will use the formulas for a binomial distribution.
For part (c) of the question:
(i) The mean can be calculated using the formula for the mean of a binomial distribution:
Mean = n * p
where n is the total number of trials and p is the probability of success in each trial.
In this case, the total number of cars stopped for inspection is 379 and the probability of a car having unsafe tires is 15% or 0.15.
Mean = 379 * 0.15 = 56.85 (rounded to one decimal place)
(ii) The standard deviation can be calculated using the formula for the standard deviation of a binomial distribution:
Standard deviation = sqrt(n * p * (1 - p))
where sqrt represents the square root operation.
Using the same values for n and p as above:
Standard deviation = sqrt(379 * 0.15 * (1 - 0.15)) = 6.79 (rounded to two decimal places)
For part (d) of the question:
(i) The mean can be calculated using the same formula as before, with the total number of seeds being 60 and the probability of germination being 0.89.
Mean = 60 * 0.89 = 53.4 (rounded to one decimal place)
(ii) Similarly, the standard deviation can be calculated using the same formula as before, using the values for n and p as above:
Standard deviation = sqrt(60 * 0.89 * (1 - 0.89)) = 3.10 (rounded to two decimal places)
Remember that the formulas used here are specific to the binomial distribution.