9
Answer: DSet 2: Linear Inequalities (Advanced)
Explanation
PROBLEM
A test has 50 questions. Each correct is +2, wrong is -1. Minimum correct to score 70 or more?
A test has 50 questions. Each correct is +2, wrong is -1. Minimum correct to score 70 or more?
A.
45
B.
35
C.
38
D.✓ Correct
40
Detailed Explanation
Choice D is the best answer. 2c - (50-c) >= 70. 3c >= 120, c >= 40
Why others are wrong:
A: 45 is incorrect because it does not satisfy the equation.
B: 35 is incorrect because it does not satisfy the equation.
C: 38 is incorrect because it does not satisfy the equation.