Answer:
Experiment 1 and 3 are clear binomial experiments.
Experiment 2 needs tweaking to be a binomial experiment.
Check Explanation.
Step-by-step explanation:
A binomial experiment is one in which
1) The probability of success doesn't change with every run or number of trials.
2) It usually consists of a fixed number of runs/trials with only two possible outcomes, a success or a failure.
3) The outcome of each trial/run of a binomial experiment is independent of one another.
Checking each of the experiments one at a time
- You observe the gender of the next 850 babies born at a local hospital. The random variable represents the number of boys.
For this experiment,
1) The probability of success doesn't change with every run or number of trials as it is a 50% chance that each child examined is a boy.
2) It consists of a fixed number of runs (850) with only two possible outcomes, success (if it's a boy) and failure (if it's a girl).
3) The probability of each trial being a boy is independent from all the other trials.
Hence, this experiment is a binomial experiment.
- You draw a marble 350 times from a bag with three colors of marbles. The random variable represents the color of marble that is drawn.
For this experiment,
1) If the marbles aren't being replaced after each draw, the probability of success, that is, picking a particular marble colour changes from trial to trial.
2) Although, it consist of a fixed number of runs/trials, there are more than two possible outcomes with 3 types of colours. Unless the experiment focuses on one colour and treats the other two colours as 'others', this condition too isn't satisfied.
3) Without replacement, the probability of success (picking a particular marble colour) in one trial isn't independent of the other trials.
This is not a binomial experiment as it doesn't satisfy all the required conditions to be one.
- Testing a cough suppressant using 820 people to determine if it is effective. The random variable represents the number of people who find the cough suppressant to be effective.
1) The probability of success doesn't change with every run or number of trials as it is the same chance that each person finds the cough suppressant to be effective.
2) It consists of a fixed number of runs (820) with only two possible outcomes, success (cough suppressant is effective) and failure (cough suppressant isn't effective).
3) The probability of each trial being a person that finds the cough suppressant to be effective, is independent from all the other trials.
Hence, this experiment is a binomial experiment.
Hope this Helps!!!
