The average of 5 marks is 72. Four of the marks are 65, 70, 75 and 80. What is the fifth mark?
A$60$
B$65$
C$70$
D$78$
Answer & Solution
Correct answer: C. $70$
Total = 5 × 72 = 360. Sum of given four = 65 + 70 + 75 + 80 = 290. Fifth mark = 360 − 290 = 70.
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