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In a multiple choice test, there are 20 questions. For each question, 5 marks are given for each correct answer, 3 marks are deducted for each incorrect answer and 1 mark is deducted for no answer. Mary attempts 16 questions and her final score is 44. Find the number of correct answers Mary got in the test.

最佳解答:

Let x and y be the number of questions attempted with correct answers and wrong answers respectively. Then x + y = 16 (Total number of questions attempted) 5x - 3y - 4 = 44 (Total score is 44) Solve it and you will get x = 12 and y = 4 So the number of correct answers Mary got in the test is 12.

其他解答:

let X be the number of correct answers wrong answer= 20-4-x ....................=16-x 5x-4-3(16-x)=44 5x-4-48+3x=44 5x-52+3x=44 8x=96 x=12 so, the number of correct answers Mary got in the test is 12
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