Mathematics
NULL
Medium
Question
A class averages 80 in an exam. Excluding 5 students who average 40, the rest average 90. How many students wrote the exam?
A
20
B
15
C
25
✓ Official correct answer
D
35
Community credibility
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A
20
No member explanations yet for this option.
B
15
No member explanations yet for this option.
C
25
No member explanations yet for this option.
D
35
No member explanations yet for this option.
Explanation
80n − 200 = 90(n − 5) ⇒ n = 25.