8. William got scores of 91, 92, and q3 on three quizzes. a. Write a formula for the average x of all three quizzes.

b. William got an 85 and an 88 on the first two quizzes.

What formula can William use to determine the score he needs on the third quiz to get an average of 90?

What score does he need?​

I am thinking you mean 93 to represent William's scores of 91, 92, and "q3"on three quizzes in Queston 8a

Average (x)= 92

b.William needs 97 as his third score to get as average of 90

Step-by-step explanation:

a.

The  Average ( x) of the scores  can solved using the Formulae

Average ( x)= Sum of  scores / Number of Scores

Average ( x) = (Score 1 + Score 2 + Score 3) /3

Average (x)= (91, 92, and 93 )/3=276/3 = 92

b) Average ( x) of the scores = Sum of  scores/ Number of Scores

Now  let Score be represented  as  S  such that

Average (x) = (S 1 + S 2 +  S3  )/ 3

90 = 85+ 88+ S/ 3

90 x 3= 85+ 88 + S

270=173+ S

S= 270- 173

S=97

William needs 97 as his third score to get as average of 90