Answer:
982
Step-by-step explanation:
The teacher is asking for the smallest number which fits the statement. 982 is correct because it is only one more than 981.
Answer:
The probability that at least 280 of these students are smokers is 0.9664.
Step-by-step explanation:
Let the random variable <em>X</em> be defined as the number of students at a particular college who are smokers
The random variable <em>X</em> follows a Binomial distribution with parameters n = 500 and p = 0.60.
But the sample selected is too large and the probability of success is close to 0.50.
So a Normal approximation to binomial can be applied to approximate the distribution of X if the following conditions are satisfied:
1. np ≥ 10
2. n(1 - p) ≥ 10
Check the conditions as follows:

Thus, a Normal approximation to binomial can be applied.
So,

Compute the probability that at least 280 of these students are smokers as follows:
Apply continuity correction:
P (X ≥ 280) = P (X > 280 + 0.50)
= P (X > 280.50)

*Use a <em>z</em>-table for the probability.
Thus, the probability that at least 280 of these students are smokers is 0.9664.
Your question is incomplete i guess
Given:
Population mean, μ = 10
Population standard deviation, σ = 1.5
Random variable, x = 11.
By definition, the z-score is
z = (x - μ)/σ
= (11 - 10)/1.5
= 0.667
Answer: 0.667
Just add the numbers then subtract from 12