Andrew has these marks: English 82%, French 75%, History 78%, Science 80%
a) What mark will Andrew need in math if he wants his mean mark to be each percent?
i) 80% ii) 81% iii) 82%
b) Is it possible for Andrew to get a mean mark of 84% or higher? Justify your answer.
a)
i - In order for Andrew to average 80% in 5 subjects, he would have to score 85% in Math.
ii-...................................................81%.............................................................90% .............
iii-..................................................82%..............................................................95%..............
b) If the maximum mark is 100%, then it is NOT possible for Andrew to get an average of 84%, since he would need a score of 105% in Math, which I assume is not allowed.
Here's a (i) .....the other two are worked the same way
Average = 80 ...so.....
[ 82 + 75 + 78 + 80 + ? ] / 5 = 80 multiply by 5
82 + 75 + 78 + 80 + ? = 400
315 + ? = 400
? = 400 - 315 = 85 is the % he needs
b 84 * 5 = 420........he only has 315...so...he needs 105 (%) on the last test.....impossible