1. A quality engineer wants to check the quality of steel rods produced in a steel factory. For this, 40 pieces of steel rods are randomly selected from the steel factory to assess their quality. Based on this, choose the correct option below
2. Which of the following statements is (are) true:
3. Values of temperature and humidity of a room are measured for 24 hours at a regular time interval of 30 minutes. Based on this, choose the correct option from below:
Answers
1- C ; 2- A, C, D ; 3- B
Explanation:
1. Option C is correct; The population is all steel rods produced in the given steel factory; the sample is the 40 steel rods selected from the given steel factory’s production.
By definition, population is the entire collection of elements we are interested in. Here, the engineer wants to check the quality of steel rods produced in the given steel factory. Hence, population will be all steel rods produced in the given factory. Sample is a subset of the population which is being studied. Since the engineer is studying only a set of 40 rods collected from that factory, the sample is the set of 40 selected steel rods.
2. Option A: All basic mathematical operations can be performed on some structured data, C: Email contents, text messages, and audio files are usually unstructured data, D: Height(cm), Weight(Kg), Age(years) are structured data are correct.
Option (A) Consider the income of employees of a certain company. It is certainly a structured data and we can perform mathematical operations such as mean and/or sum on the income of employees.
Option (B) Unstructured data may not necessarily have numeric properties; therefore, 1 in general, mathematical operations can not be performed on unstructured data.
Option (C) Email contents, text messages or audio files can not be organized in any specific way as these do not have any inherent order; therefore, these are unstructured data.
Option (D) Height, weight, and age have definite order and can always be arranged in an order. Hence, they are structured data.
3. Option B is correct; It is time series data.
Since the humidity and temperature are recorded over a certain period of time and at regular intervals, and thus the data collected is time series data.