Suppose the mean percentage in Algebra 2B is 70% and the standard deviation is 8%. What percentage of students end up with less than a 78%?

Answer 1

σ=70%, μ=8%. 78% of full grade = σ+μ

A graph of normal distribution shows that there are 100 - (13.6+2.1+.1) = 100 - 15.8 = 84.2% of the population below σ+μ

Answer is 84.2%