The marks (out of 100) obtained by a group of students in Mathematics test are :
88, 74, 90, 88, 40, 46, 58, 96, 82, and 78. Find :
mean marks obtained by the group

Answer

To find the mean marks obtained by the group of students, we will follow these steps:

### Step 1: List the marks obtained by the students.
The marks obtained by the students are:
- 88
- 74
- 90
- 88
- 40
- 46
- 58
- 96
- 82
- 78

### Step 2: Calculate the sum of the marks.
We will add all the marks together:
\[ 88 + 74 + 90 + 88 + 40 + 46 + 58 + 96 + 82 + 78 \]

Calculating the sum step-by-step:
- \( 88 + 74 = 162 \)
- \( 162 + 90 = 252 \)
- \( 252 + 88 = 340 \)
- \( 340 + 40 = 380 \)
- \( 380 + 46 = 426 \)
- \( 426 + 58 = 484 \)
- \( 484 + 96 = 580 \)
- \( 580 + 82 = 662 \)
- \( 662 + 78 = 740 \)

So, the total sum of the marks is **740**.

### Step 3: Count the number of observations (students).
There are **10** students in total.

### Step 4: Calculate the mean.
The formula for the mean is:
\[ \text{Mean} = \frac{\text{Sum of observations}}{\text{Number of observations}} \]
Substituting the values we found:
\[ \text{Mean} = \frac{740}{10} = 74 \]

### Conclusion:
The mean marks obtained by the group of students is **74**.

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