Question

The length of sweetpea flower stems are normally distributed with mean 18.2 cm and standard deviation 2.3 cm.

(a) Find the probability that the length of a flower stem is between 16 cm and 20 cm.

Answer: 0.6139 *I found it and, it's correct*.

(b) 12% of the flower stems are longer than h cm. 20% of the flower stems are shorter than k cm. Find h and k.

*Need Help*

Answer 1

h = 20.9
k = 16.26

you have to use a standard normal table or lookup software
if 12% are longer, then 88% are shorter...look up .88 find Z-value
Z = (h-18.2)/2.3
For k do same thing ...look up 0.2 find Z-value
Z = (k-18.2)/2.3