SOLUTION: in an examination, a student attempted 15 question correctly and secured 40 marks. if there were two types of question (2 marks and 4 marks), how many questions of 2 marks did he a

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Question 1009472: in an examination, a student attempted 15 question correctly and secured 40 marks. if there were two types of question (2 marks and 4 marks), how many questions of 2 marks did he attempt correctly?solve
Found 2 solutions by rothauserc, stanbon:
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
let x be questions of 2 marks and let y be questions of 4 marks, then
x + y = 15
2x + 4y = 40
solve first equation for y
y = 15 - x
substitute for y in second equation
2x + 4(15-x) = 40
2x + 60 - 4x = 40
-2x = -20
x = 10
there were 10 questions of 2 marks attempted correctly

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
in an examination, a student attempted 15 question correctly and secured 40 marks. if there were two types of question (2 marks and 4 marks), how many questions of 2 marks did he attempt correctly?
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Equation:
4*(15-x) + 2x = 40 points
60-4x + 2x = 40
-2x = -20
x = 10 (# of 2-mark questions attempted)
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Cheers,
Stan H.
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