Examination 2

In an examination, a teacher awards 2 marks for every correct answer and subtract a mark for every wrong answer. If there are 20 questions and a child scored 25 marks how many correct answer did the child get?

Result

c =  15

Solution:


25 = 2c - 1*(20-c)

3c = 45

c = 15

Calculated by our simple equation calculator.







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To solve this example are needed these knowledge from mathematics:

Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation?

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