Answer:
The next score he needs to have an overall average of 79 is 89.
Step-by-step explanation:
Gary earned an average score of 77 on his 5 quizzes . The number of score he needs to have an average of 79 can be calculated below.
average score = 77
number of quizzes = 5
sum of Garry score = a
a/5 = 77
cross multiply
a = 77 × 5
a = 385
let
the next score he needs be b to score an average of 79
average = 79
number of quizzes = 6
385 + b/6 = 79
cross multiply
385 + b = 474
b = 474 - 385
b = 89
The next score he needs to have an overall average of 79 is 89.
