I need some help with this problem:
"After having corrected all but the final test result in a class of n students, the teacher finally grades the last test and finds that the mean test score in the class increased by 0.75 and that the final test result had a score 18 points higher than the previous mean, before the last test was corrected. How big is the class?"
I basically just used the following equation...
m * (n - 1) + (m + 18)
/
n
=
m + 0.75,
and ended up getting n = 18/(0.75) = 24, however apparently the answer is 25... can someone help me with this?
"After having corrected all but the final test result in a class of n students, the teacher finally grades the last test and finds that the mean test score in the class increased by 0.75 and that the final test result had a score 18 points higher than the previous mean, before the last test was corrected. How big is the class?"
I basically just used the following equation...
m * (n - 1) + (m + 18)
/
n
=
m + 0.75,
and ended up getting n = 18/(0.75) = 24, however apparently the answer is 25... can someone help me with this?
