Answer: mean = 64.95
Step-by-step explanation:
According to the Empirical rule , 95% of the population lies with 2 standard deviations from the mean when data is normally distributed.
Given: 95% of all marigold flowers have a height between 10.9 cm and 119.0 cm.
If height is normally distributed , then
Mean - 2 standard deviation = 10.9 (i)
Mean + 2 standard deviation = 119.0 (ii)
Add (i) and (ii), we get
2 Mean = 10.9+119.0
⇒ 2 Mean = 129.9
⇒ Mean = 64.95 [divide both sides by 2]
So, mean = 64.95
