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Harlamova29_29 [7]

3 years ago

9

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?

2 answers:

Maksim231197 [3]3 years ago

8 0

X + y = 24....multiply by -3
3x + 5y = 100
---------------
-3x - 3y = - 72 (result of multiplying by -3)
3x + 5y = 100
--------------add
2y = 28
y = 28/2
y = 14

x + y = 24
x + 14 = 24
x = 24 - 14
x = 10

solution is (10,14)...and x represents 3 point q's and y represents 5 point q's......so this tells me there are 10 three point q's and 14 five point q's.

mart [117]3 years ago

6 0

Answer:

The answer is B) The test contains 10 three-point questions and 14 five-point questions.

Step-by-step explanation:

Hope this helps!

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