Answer:
0.9544
Step-by-step explanation:
We are given that mean=18 and standard deviation=1 and we have to find P(16<X<20).
P(16<X<20)=P(z1<Z<z2)
z1=(x1-mean)/standard deviation
z1=(16-18)/1=-2
z2=(x2-mean)/standard deviation
z2=(20-18)/1=2
P(16<X<20)=P(z1<Z<z2)=P(-2<Z<2)
P(16<X<20)=P(-2<Z<0)+P(0<Z<2)
P(16<X<20)=0.4772+0.4772=0.9544
The probability that the height of a tree is between 16 and 20 feet is 95.44%
Step 2 is wrong: 4x - x = 5x
X = -11 is the actual answer, pretty sure.
Hope this helps and please mark as brainliest. If you have any other doubts, feel free to ask.
I believe 11 centimeters is the answer.