A brochure claims that the average maximum height for a certain type of plant is 0.7 m. A gardener suspects that this is not accurate locally due to variation in soil conditions, and believes the local height is shorter. A random sample of 40 mature plants is taken. The mean height of the sample is 0.65 m with a standard deviation of 0.20 m. Test the claim that the local mean height is less than 0.7 m using a 5% level of significance.

As , it is possible to reject null hypotesis. It means that the local mean height is less tha 0.7 m with a 5% level of significance.

Step-by-step explanation:

1. Relevant data:

2. Hypotesis testing

3. Find the rejection area

From the one tail standard normal chart, whe have Z-value for is 1.56

Then rejection area is left 1.56 in normal curve.

4. Find the test statistic:

5. Hypotesis Testing

As , it is possible to reject null hypotesis. It means that the local mean height is less tha 0.7 m with a 5% level of significance.

96 39 cause 135 -96=39 im smart (i used a calculater)