The heights of the trees in a forest are normally distributed, with a mean of 25 meters and a standard deviation of 6 meters. What is the probability that a randomly selected tree in the forest has a height greater than or equal to 37 meters? Use the portion of the standard normal table given to help answer the question.

\begin{tabular}{|c|c|}
\hline
[tex]$z$[/tex] & Probability \\
\hline
0.00 & 0.5000 \\
\hline
0.50 & 0.6915 \\
\hline
1.00 & 0.8413 \\
\hline
2.00 & 0.9772 \\
\hline
3.00 & 0.9987 \\
\hline
\end{tabular}

A. [tex]$0.13 \%$[/tex]
B. [tex]$0.26 \%$[/tex]
C. [tex]$3 \%$[/tex]
D. [tex]$4.6 \%$[/tex]



Answer :

To determine the probability that a randomly selected tree in the forest has a height greater than or equal to 37 meters, we can follow these steps:

### Step-by-Step Solution:

1. Identify the given values:
- Mean height ([tex]\(\mu\)[/tex]) = 25 meters
- Standard deviation ([tex]\(\sigma\)[/tex]) = 6 meters
- Tree height ([tex]\(X\)[/tex]) = 37 meters

2. Calculate the z-score for the tree height of 37 meters:
- The z-score formula is given by: [tex]\( z = \frac{X - \mu}{\sigma} \)[/tex]
- Substituting the given values:
[tex]\[ z = \frac{37 - 25}{6} = \frac{12}{6} = 2.0 \][/tex]

3. Find the cumulative probability for the z-score from the standard normal table:
- We look up the probability for [tex]\( z = 2.0 \)[/tex] in the provided table:
[tex]\[ \text{Probability for } z = 2.0 \text{ is } 0.9772 \][/tex]

4. Interpret the cumulative probability:
- The cumulative probability of 0.9772 represents the probability that a tree is shorter than 37 meters.

5. Compute the probability that a tree is taller than or equal to 37 meters:
- Since the cumulative probability represents [tex]\( P(X < 37) \)[/tex], we need [tex]\( P(X \geq 37) \)[/tex]:
[tex]\[ P(X \geq 37) = 1 - P(X < 37) = 1 - 0.9772 = 0.0228 \][/tex]

6. Convert this probability to a percentage:
- We multiply the decimal probability by 100 to get the percentage:
[tex]\[ 0.0228 \times 100 = 2.28\% \][/tex]

Therefore, the probability that a randomly selected tree in the forest has a height greater than or equal to 37 meters is 2.28%.

Among the provided options, the one closest to 2.28% is:

[tex]\[ \boxed{3\%} \][/tex]