The score x represents the score of the science test Finn has yet to take.

Question

If Finn wants to have the same mean score in science as in history, what score must he achieve on his last science test?

History test scores: 78, 65, 72, 85, 68, 70, 80, 82

Science test scores: 78, 45, 80, 88, 80, 78, 62, x

The mean in history is 75.

Answer 1

sum of 7 science grades = 511

sum of 8 history grades =600

600-511 = 89

He needs an 89 on the next science test to get the same average

600/8 = 75

(511+89)/8 = 75