Tom wants to know the average number of musical instruments students in his school play. He used the school's two band classes, consisting of a total of 48 students, as his representative sample. He concluded that students in his school play an average of three musical instruments. Is his conclusion valid? (1 point)
No, because he did not choose students randomly.
No, because his representative sample is too large.
Yes, because the sample includes both males and females who play musical instruments.
Yes, because all members of the sample play at least one musical instrument.
No, because he did not choose students randomly.
A survey is conducted to determine the most common reason people own a cell phone. A company sent out a survey to customers between the ages of 20 and 30. Based on the responses, the company concluded that people own a cell phone for messaging purposes. Is this conclusion valid? (1 point)
No, because the sample includes customers of too many different ages.
No, because not all people who own a cell phone have the same probability of being selected.
O Yes, because the sample includes all customers between the ages of 20 and 30.
Yes, because the sample includes male and female customers.
No, because not all people who own a cell phone have the same probability of being selected.
A school principal wants to know the average number of extracurricular activities students in her school are involved in. She assigned each student a number from 1 to 415. Using a random number generator, she selected 200 students to be part of the sample. She concluded that students are involved in an average of two extracurricular activities. Is the principal's conclusion valid? (1 point)
Yes, because every student had an equal chance to be part of the sample. The sample size also appears to be large enough.
Yes, because only those who have extracurricular activities were included in the sample.
No, because 200 students in the sample is too large.
No, because not all students in the sample have extracurricular activities.