Nope, the answer for (a) is 27.
To find (b), 27×3
Answer:
65
Step-by-step explanation:
yessss
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.
<span>arc length = circumference • [central angle (degrees) ÷ 360]
Solving this equation for circumference:
</span>
<span>circumference = arc length / (central angle / 360)
</span><span>circumference = 12 / (85/360)
</span>circumference = 12 / <span><span>0.2361111111
</span>
</span>
<span>circumference =
</span>
<span>
<span>
<span>
50.8235294118
</span>
</span>
</span>
Source:
http://www.1728.org/radians.htm