SOLUTION: A boy sat for a test containing 20 questions. He was awarded two marks for each correct answer and one mark was subtracted for each incorrect answer. a) Let n be the number of que

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Question 785386: A boy sat for a test containing 20 questions. He was awarded two marks for each correct answer and one mark was subtracted for each incorrect answer.
a) Let n be the number of questions he answered correctly. Write a formula to calculate his score (S) on the test.

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
n correct
so 20-n incorrect
S= 2n-1(20-n)
S=2n-20+n
S=3n-20