The given problem describes a binomial distribution with p = 60% = 0.6. Given that there are 400 trials, i.e. n = 400.
a.) The mean is given by:

The standard deviation is given by:

b.) The mean means that in an experiment of 400 adult smokers, we expect on the average to get about 240 smokers who started smoking before turning 18 years.
c.) It would be unusual to observe <span>340 smokers who started smoking before turning 18 years old in a random sample of 400 adult smokers because 340 is far greater than the mean of the distribution.
340 is greater than 3 standard deviations from the mean of the distribution.</span>
Answer:
2.9
Step-by-step explanation:
To answer this question, you need to draw out the graph first. By doing so, you will be able to know where the other endpoint is located. (Fig. 1)
Next, count the number from the midpoint to the endpoint to determine the coordinates for the other endpoint. (Fig. 2)
Example: From (2, 5) to (6, 3)
x: 2 to 6 = 4 steps
y: 5 to 3 = 2 steps
From there, you can determine the other endpoint like this.
Example: From (2, 5) to the other endpoint
x: 2 to x1 = 4 steps
y: 5 to y1 = 2 steps
Therefore, x1 = -2 and y1 = 7
Other endpoint: (-2, 7)
Sorry for the messy drawing, it is hard to draw without a pen. Haha... hope this helps :)
2. is 4/2 or 2 3.is 12/4 or 3 4.is 5 wholes