Question

The scores of eight grade students in a math test are normally distributed with a mean of 57.5 and a standard deviation of 6.5. From this data, we can conclude that 68% of the students recieved scores between

a)34 and 64
b)34 and 68
c)51 and 64
d)51 and 68

Answer 1

work out the z scores for 51 and 54
z1 = (51 - 57.5) / 6.5 = -1
z2 = (64 - 57.5)/6.5 = 1
from tables of normal distribution this value os 3413 + 3413 = 68.26%


so the answer is c