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.

17

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

$x$

Now, substitute the values into the mean formula:

30 = (283 + x ) /10

300 = 283 + x

x = 300- 283 = 17

$x$