A science test, which is worth 100 points, consists of 24 questions. Each question is worth either 3 points or 5 points. If x is
the number of 3-point questions and y is the number of 5-point questions, the system shown represents this situation. x + y = 24 3x + 5y = 100 What does the solution of this system indicate about the questions on the test?
The test contains 4 three-point questions and 20 five-point questions.
The test contains 10 three-point questions and 14 five-point questions.
The test contains 14 three-point questions and 10 five-point questions.
The test contains 20 three-point questions and 8 five-point questions.
The test contains 4 three-point questions and 20 five-point questions.
The test contains 10 three-point questions and 14 five-point questions.
The test contains 14 three-point questions and 10 five-point questions.
The test contains 20 three-point questions and 8 five-point questions.
2 answers:
Answer:
The test contains 10 three-point questions and 14 five-point questions.
Step-by-step explanation:
The value of x is the number of 3-point questions, and the value of y is the number of 5-point questions, as the problem statement tells you. So, the solution (x, y) = (10, 14) indicates ...
"The test contains 10 three-point questions and 14 five-point questions."
_____
You can try the offered answers to see which might apply. The last choice has too many questions. The first and third choices don't add up to 100 points.
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is a solution for this recurrence, with 
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So we expect a general solution of the form
With
, we get four equations in four unknowns:
So the particular solution to the recurrence is
(b) Let
be the generating function for 
. Multiply both sides of the recurrence by 
and sum over all 
.
From here you would write each term as a power series (easy enough, since they're all geometric or derived from a geometric series), combine the series into one, and the solution to the recurrence will be the coefficient of, ideally matching the solution found in part (a).
So we expect a general solution of the form
With
So the particular solution to the recurrence is
(b) Let
From here you would write each term as a power series (easy enough, since they're all geometric or derived from a geometric series), combine the series into one, and the solution to the recurrence will be the coefficient of