Two tailed hypothesis test using the Z value | Standard Normal Curve| Leaving Cert Maths |

Task:
In 2016, 150 of the 15 year olds in that country were randomly selected and their weights recorded. It was found that their weights were normally distributed with a mean weight of 62 kg and a standard deviation of 10 kg. Test the hypothesis, at the 5% level of significance, that the mean weight of 15 year olds, in that country, had not changed from 2015 to 2016. State the null hypothesis and your alternative hypothesis.
Give your conclusion in the context of the question.

Given information:
In 2015, in a particular country, the weights of 15 year olds were normally distributed with a mean of 63·5 kg and a standard deviation of 10 kg.

Step1: Null hypothesis and the alternative hypothesis are stated.
Step2: If the Z value for the sample lies within the shaded area under the tails of standard normal curve then reject the null hypothesis.
Step3: In this example the z value from the sample, did not fall into the red zone therefore Null hypothesis is valid and the mean has not changed.
***************************************
Leaving Cert | HL| Exam | 2017 B | Q8a(iii)
***************************************
Contents:
(1) Introduction
(2) Method
(3) Solution
(4) Key points
***************************************

#LeavingCert#Maths |#SolveD124 | SolveD124

Видео Two tailed hypothesis test using the Z value | Standard Normal Curve| Leaving Cert Maths | канала thinkeccel