Sample and Population By: Group 5 START! 1. Altafiyani Rahmatika 2. Gina Nuryustika Rizal 3. Jody Furqon Sanjaya 4. Wini Safitri Class IX D
Select! 1.DEFINITION 2. SAMPLE AND POPULATION IN DAILY LIFE 3.THESAMPLING PROCESS 4. EXAMPLE 5. EXERCISE
DefinitionWhat is the meaning of And, what is the meaning of sample? population? Sample is a part of Population is all objects population being studied being studied. or observed.
Sample and Population in Daily Life Suppose we want to know the average weight of Junior HighSchool students in Subang. Considering limited time, labor andcost, we cannot measure all the students. Thus, we should pick arandom sample consisting of all students from a number ofpublic or private schools. In this case :i. all Junior High School students in Subang constitute the population,ii. Students whose heights are measured constitute the sample.
The Sampling Process POPULATION (N) INFERENCE • Define population (N) to be SAMPLE (n) sampled • Determine sample (n) from population (N) to be observed • Determine an inference of population based on sample
Example 1 SMP B has 8 classes of students from each grade VII,VIII, IX. Suppose that the principal wants to conduct aresearch on the relation between parental socioeconomicstatus and a student’s outcome, determine:a. the populationb. the sample Answer: a. The population is all the students in SMP B. b. The sample is some students from each grade VII, VIII, and IX selected randomly.
Example 2A research has been carried out to determine the pollutionlevel in a lake.a. What is the population?b. How to collect the sample?Answer:a. The population is a lake.b. A research only observe some quantities of water taken randomly as the sample of the lake (population) to determine the pollution level in a lake.
Exercise1. The department of National Education is conducting a research on the result of the national final exam in a province. Determine. a. the population b. the sample Answer: a. The population is the result of the national final exam in a national (all province) b. The sample is the result of the national final exam in a province.
2. A farmer cultivate his ½ ha rice field. Being properly cultivated, the rice field yields good quality crop. In harvest time, he gets 8 kg of unhusked rice field totaling 10 m2 in area. a. What is the population? b. What is the sample? c. Based on the sample, estimate the total mass of unhusked rice grains the farmer can harvest Answer : a. The population is ½ ha rice field. b. The sample is 8 kg of unhusked rice grains from different parts of his rice field totalling 10 m2 of rice field.
c. The population = ½ ha rice field = ½ hm2 = ½ x 10000 = 5000 m2 The sample = 8 kg of 10 m2 in area of ½ ha rice field = 8 kg/10 m2 The total mass of unhusked rice grains = Sample x Population = x 5000 m2 2 = 4000 kg Thus, the total mass of unhusked rice grains the farmer can harvest is 4000 kg.