The score of the seventh student will be given by:
[tex]x = 546 - a_1 - a_2 - a_3 - a_4 - a_5 - a_6[/tex]
What is the score of the last student?
So you know the scores of 6 of the students, let's define these as:
a₁, a₂, a₃, a₄, a₅, a₆.
And let's define x as the score of the 7th student.
We know that the average of the scores is 78% (rounded).
Then we can estimate the value of x using the average equation:
[tex]\frac{a_1 + a_2 + a_3 + a_4 + a_5 + a_6 + x}{7} = 78[/tex]
Now you can solve that for x, to get:
[tex]x = 78*7 - a_1 - a_2 - a_3 - a_4 - a_5 - a_6\\\\x = 546 - a_1 - a_2 - a_3 - a_4 - a_5 - a_6[/tex]
That is the equation to get the score of the seventh student as a function of the six known scores.
If you want to learn more about averages, you can read:
https://brainly.com/question/14532771
