Answer
at first I said 1/2 but it's 2/5's.
Step-by-step explanation:

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.
S = 10 + r
s + r = 100
Adding equations,
2s +r = 110 + r
2s = 110
s = 55
r = 45
0
evaluate g(7) by substituting x = 7 into g(x
g(7) = (49-35-10)/2 = 4/2 = 2
now substitute x = 2 into f(x)
f(2) = √(4 - 48 + 144) = √0 = 0
(f ○ g)(7) = 0