A quality control manager wants to determine the percentage of defective light bulbs in the production line. Which of the following sampling methods would most likely lead to a valid inference?(1 point)
Responses
testing the first 2,000 light bulbs in the production line
testing the first 2,000 light bulbs in the production line
testing every fiftieth light bulb in the production line
testing every fiftieth light bulb in the production line
testing the last 4,000 bulbs in the production line
testing the last 4,000 bulbs in the production line
retesting 100 light bulbs that have already been tested
testing every fiftieth light bulb in the production line
Avery randomly selects 50 colored pencils from a basket and finds that 2 are not sharpened. If the basket contains 300 colored pencils, how many would you expect to be unsharpened?(1 point)
Responses
12
12
2
2
20
20
120
12
There are 628 students in Tan’s high school. Tan surveys 120 randomly chosen students about their favorite movie genre. The results are as follows.
Movie genre Number of students/Frequency
Science Fiction 24
Horror 11
Comedy 27
Action 10
Animated 48
Based on Tan’s sample data, approximately how many students in the school prefer animated movies?
(1 point)
Approximately 121 students prefer animated movies.
To find out, we can use the concept of proportions.
We know that 120 students were surveyed, and 48 of them preferred animated movies.
So, in terms of proportion:
48/120 = x/628
Simplifying this proportion, we get:
x = (48*628)/120
x = 251.2
So, approximately 251 students in the school prefer animated movies.
There are 528 students in Pablo’s high school. Pablo surveys 130 randomly chosen students about their favorite ice cream flavor. The results are as follows.
Ice cream flavor Number of students/Frequency
Strawberry 29
Butter Pecan 31
Chocolate 43
Orange Sherbet 10
Vanilla 17
Based on Pablo’s sample data, approximately how many students in the school prefer orange sherbet?
(1 point)
Approximately 49 students in the school prefer orange sherbet.
To find out, we can use the concept of proportions.
We know that 130 students were surveyed, and 10 of them preferred orange sherbet.
So, in terms of proportion:
10/130 = x/528
Simplifying this proportion, we get:
x = (10*528)/130
x = 40.8
So, approximately 41 students in the school prefer orange sherbet.
The temperatures (in °F) in a city on randomly selected days during the summer are 89, 85, 90, 87, 86, 91, 88, and 89. What is the mean temperature? Round your answer to one decimal place.(1 point)
The mean temperature is 87.6°F.
To find the mean, we need to add up all the temperatures and divide by the total number of temperatures:
89 + 85 + 90 + 87 + 86 + 91 + 88 + 89 = 605
605/8 = 75.625
Rounding to one decimal place, we get 87.6°F.