math
posted by jonathan on .
there are 50 question in a test. a student gains 2 marks for a correct anwser and loses 1 mark otherwise. if a student has 76 marks, how many question did he answer incorrectly?

This is fairly easy just use alittle more effort and someone will check your answer.

i = # incorrect (or otherwise) answers
c = # correct answers
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i + c = 50
1 + 2c = 76
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Solve the two equations simultaneously.
Post your work if you get stuck. 
Check my thinking. Check my work.