#3.......the 3 with the m makes it greater than 1
C i believe, hope it helps
Answer:
z = 4
Step-by-step explanation:
12z - 18 = 30
add 18 to both sides:
12z = 48
divide by 12:
z = 4
According to the empirical rule, approximately 68% of data fall within 1 standard deviation of the mean.