You don't need to know any trig to select the correct answer. You only need to know that the lengths of both sides must be less than the length of the hypotenuse. It is also helpful to know that √3 is about 1.732, so 10√3 ≈ 17.32.
Since x < 10√3, only answer choices A and D are viable.
Since y < 10√3, only answer choice D is viable.
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If you want to solve this using trig relations, you can recall that the sides of a 30°-60°-90° triangle have the ratios 1 : √3 : 2. This means short side y is half the length of the hypotenuse 10√3, so y = 5√3. It also means longer side x is √3 times y, so is x = (5√3)√3 = 5·3 = 15.
11.44% probability that exactly 12 members of the sample received a pneumococcal vaccination.
Step-by-step explanation:
For each adult, there are only two possible outcomes. Either they received a pneumococcal vaccination, or they did not. The probability of an adult receiving a pneumococcal vaccination is independent of other adults. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
In which is the number of different combinations of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
70% of U.S. adults aged 65 and over have ever received a pneumococcal vaccination.
This means that
20 adults
This means that
Determine the probability that exactly 12 members of the sample received a pneumococcal vaccination.
This is P(X = 12).
11.44% probability that exactly 12 members of the sample received a pneumococcal vaccination.