Mean marks obtained by 10 students is 30.
The marks obtained are: 25, 30, 21, 55, 47, 10, 15, x, 45, 35.
Find the value of x.
Answer & explanation
Correct answer: option 2
The correct answer is Option 2: 17
The formula for the mean (average) is:
Mean=Sum of all values/ Number of values
Given:
- Mean =30
- Number of students =10
Sum of marks (excluding x) = 25 + 30 + 21 + 55 + 47 + 10 + 15 + 45 + 35 =283
Now, substitute the values into the mean formula:
30 = (283 + x ) /10
300 = 283 + x
x = 300- 283 = 17
Therefore, the value of x is 17.