Question #3ef43

1 Answer
Jul 20, 2017

Answer:

New mean #= 94.3#

Explanation:

The formula to calculate mean is:

#"Mean" = "Total of values"/"number of values" " "M = T/N#

This means we also have the formulae

#T = MxxN and N = T/M#

If the mean of 6 tests was #95#, then the total was:

#T=90xx6 = 570#

If the student writes another test, the total will increase and the number of tests increases.

New total# = 570+90 =660#

New number # = 6+1 = 7#

We expect the new mean to be lower, because the last test score was less than the average for the first #6#.

#Mean = 660/7 =94.2857#

#Mean = 94.3#