Question

The mean mark obtained by 7 students in a group is 226. If the marks obtained by six of them are 340, 180, 260, 56, 275 and 307 respectively, find the marks obtained by the seventh student.

Answer 1

Given:
Marks obtained by 6 students: 340, 180, 260, 56, 275 and 307
Now,
Let the marks obtained by the 7th student be x.
We know:
Mean marks obtained by 7 students = 226
Thus, we have:

$$\begin{gathered} \frac{340+180+260+56+275+307+x}{7}=226 \\ \Rightarrow \frac{1418+x}{7}=226 \\ \Rightarrow 1418+x=1582 \\ \Rightarrow x=164 \end{gathered}$$

∴ Marks obtained by the 7th student = 164