to find average add up terms divided that sum by the number of terms you have example
mean of x,y,z x+y+z 3 terms (x+y+z)/3=mean
so represent next test score as x 89+94+82+84+98+x count how many terms ther are (6 terms)
mean is 90 (89+94+82+84+98+x)/6=90 add the like terms (447+x)/6=90 multiply both sides by 6 to clear fraction 447+x=540 subtract 447 from both sides x=93
