Answer:
66 ≤ f ≤100
Explanation
Mean= ( Σ x ) / n
Mean= sum of scores/ number of subject she took
Now, she already too 3 subject which sum is 85+83+86=254
Now we need to know range of score for her to have (grade) a mark between 80 and 89
Now let take the lower limit mean=80
The lowest score she can get is
Mean = ( Σx) / n
80=(85+83+86+f)/4
80×4= 254+f
Therefore, f= 320-254=66
Therefore the minimum score she can have to have a B is 66.
Then, let take the upper limit mean 89. i.e the maximum she can have so that she don't have an A grade.
Mean = ( Σx) / n
89=( 83+85+86+f)/4
89×4= 254+f
f= 356-254
f=102.
Therefore this shows that she cannot have an A grade in the exam. The maximum score for the exam is 100.
There the range of score is 66 ≤ f ≤100 to have a B grade
66 ≤ f ≤100 answer
Since she cannot score 102 in the examination.
Answer:
532m^2
Step-by-step explanation:
Please see the attached pictures for full solution.
The standard form of a quadratic function is y = 3/2x² + 17/2x - 7
<h3>How to determine the
quadratic equation?</h3>
From the question, the points on the quadratic equation are given as
(2,4), (3,5) and (4,3)
The standard form of a quadratic equation is represented as
y = ax² + bx + c
So, we have
Point (2,4):
4a + 2b + c = 4
Point (3,5):
9a + 3b + c = 5
Point (4,3):
16a + 4b + c = 3
Solving using an online calculator. we have
a = 3/2, b = 17/2 and c = -7
Substitute a = 3/2, b = 17/2 and c = -7 in y = ax² + bx + c
y = 3/2x² + 17/2x - 7
Hence, the equation is y = 3/2x² + 17/2x - 7
Read more about quadratic equation at
brainly.com/question/1214333
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