Change set
Pick exam & year, then Go.
Question map
Not attempted
Correct
Incorrect
★
Bookmarked
Loading…
Q22
(CISF/2026)
Miscellaneous & General Knowledge › Important Days, Places & Events
The marks scored by 10 students in an examination are as follows: 30, 95, 50, 65, 70, x, 45, 75, 60, 40. If the average of the marks is 60, then what is the value of x ?
Result
Your answer:
—
·
Correct:
B
Explanation
To find the value of x, we apply the standard formula for the arithmetic mean (average):
Average = (Sum of all observations) / (Total number of observations)
According to the question:
- Total number of students (n) = 10
- Average marks = 60
- Sum of marks = 30 + 95 + 50 + 65 + 70 + x + 45 + 75 + 60 + 40
Step 1: Calculate the total sum required for an average of 60 across 10 students:
Total Sum = 10 × 60 = 600.
Step 2: Calculate the sum of the nine known values:
30 + 95 + 50 + 65 + 70 + 45 + 75 + 60 + 40 = 530.
Step 3: Solve for x:
530 + x = 600
x = 600 - 530 = 70.
The value of x is 70, which corresponds to option B.
How others answered
Each bar shows the % of students who chose that option.
Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
80%
got it right
✓ Thank you! We'll review this.