3y <= -2x+18
1 answer:
Answer:
- A (-4, -3)
- C (2, 4)
- E (3, 2)
Step-by-step explanation:
It is convenient to use technology to plot the points and the functions to see what lies where. The first attachment shows such a plot.
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Of course, you can do the function evaluations. For example, testing answer B, we find ...
... 3·6 ≤ -2·1 +18 . . . . <em>false</em> for the first equation — not a solution
Checking all the points requires 10 function evaluations. When things get repetitive like that, I like to use a graphing calculator or spreadsheet.
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<em>Using a calculator</em>
The second attachment shows a calculator evaluating the viability of each point as a solution. The equations have been rearranged to ...
- -2x -3y +18 ≥ 0
- -x +4y +12 ≥ 0
This makes it easy to look at the evaluation results to see if the solution is viable or not.
The x-values of the points are entered into list L₁ and the y-values into L₂. The result of the first inequality above is in L₃ and the result for the second inequality is in L₄. Any negative value in L₃ or L₄ shows a point that is <u>not</u> part of the solution set. Points B and D fail to match problem requirements.
Points A, C, and E are in the solution set.
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Answer:
a) 0.3921 = 39.21% probability that fewer than 14 of them have had a physical examination in the past two years.
b) 0.107 = 10.7% probability that at least 17 of them have had a physical examination in the past two years.
Step-by-step explanation:
For each women, there are only two possible outcomes. Either they visit their doctors for a physical examination at least once in two years, or they do not. The probability of a woman visiting their doctor at least once in this period is independent of any other women. This means that 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 adult women visit their doctors for a physical examination at least once in two years.
This means that
20 adult women
This means that
(a) Fewer than 14 of them have had a physical examination in the past two years.
This is:
In which
So
0.3921 = 39.21% probability that fewer than 14 of them have had a physical examination in the past two years.
(b) At least 17 of them have had a physical examination in the past two years
From the values found in item (a).
0.107 = 10.7% probability that at least 17 of them have had a physical examination in the past two years.