Answer:
79.
Step-by-step explanation:
first, you have to multiply the first amount of tests by their average score.
(5×91=455)
then you need to multiply the same way for the second set.
(6×89=534)
now we need to flip these numbers, so we can subtract to find the difference.
(6×89=534)
-(5×91=455) =79 test score.
and to fact check it you can add 79 to 455 (which is the total of the original five scores) which will give you 534, you will then divide 534 by 6 to get the average of 89.
