Spot biased and fair samples

Question 1

To check a factory's light bulbs, an inspector tests every 50th bulb made during the day. Is this sample likely to be biased?

• A. Yes, biased
• B. No, fair

Question 2

You want to find out how people in a town travel to work. Which sampling method is the fairest (least biased)?

• A. Ask drivers at a petrol station
• B. Ask cyclists in a bike shop
• C. Choose 100 households at random from the town's address list
• D. Ask people waiting at a bus stop

Question 3

To find how much students read, a teacher asks only the book club. Is this sample likely to be biased?

• A. Yes, biased
• B. No, fair

Question 4

You want to find out how people in a town travel to work. Which sampling method is the fairest (least biased)?

• A. Ask people waiting at a bus stop
• B. Ask cyclists in a bike shop
• C. Ask drivers at a petrol station
• D. Choose 100 households at random from the town's address list

Question 5

To find how much students read, a teacher asks only the book club. Is this sample likely to be biased?

• A. Yes, biased
• B. No, fair

Question 6

You want to find out which school lunch is most popular. Which sampling method is the fairest (least biased)?

• A. Ask the first 10 students in the vegetarian queue
• B. Ask the kitchen staff
• C. Ask only Year 7
• D. Ask every 10th student on the register, across all years

Question 7

To find students' favourite subject, a student council picks 40 names at random from the full school list. Is this sample likely to be biased?

• A. Yes, biased
• B. No, fair

Question 8

You want to find out how people in a town travel to work. Which sampling method is the fairest (least biased)?

• A. Ask drivers at a petrol station
• B. Choose 100 households at random from the town's address list
• C. Ask people waiting at a bus stop
• D. Ask cyclists in a bike shop

Question 9

To check a factory's light bulbs, an inspector tests every 50th bulb made during the day. Is this sample likely to be biased?

• A. Yes, biased
• B. No, fair

Question 10

You want to find out how much time students spend on sport. Which sampling method is the fairest (least biased)?

• A. Ask the football team
• B. Pick 50 names at random from the whole school list
• C. Ask people leaving the gym
• D. Ask only your friends

Question 11

To find the town's favourite sport, a reporter asks people leaving a tennis club. Is this sample likely to be biased?

• A. Yes, biased
• B. No, fair

Question 12

You want to find out how many hours of sleep teenagers get. Which sampling method is the fairest (least biased)?

• A. Ask your own class only
• B. Ask students in the library at 8 am
• C. Post a poll that only night-owl gamers see
• D. Use a random number generator to pick students from every year group

Question 13

To find the town's favourite sport, a reporter asks people leaving a tennis club. Is this sample likely to be biased?

• A. Yes, biased
• B. No, fair

Question 14

You want to find out how people in a town travel to work. Which sampling method is the fairest (least biased)?

• A. Ask cyclists in a bike shop
• B. Ask drivers at a petrol station
• C. Choose 100 households at random from the town's address list
• D. Ask people waiting at a bus stop

Question 15

To find the town's favourite sport, a reporter asks people leaving a tennis club. Is this sample likely to be biased?

• A. Yes, biased
• B. No, fair

Question 16

You want to find out how many hours of sleep teenagers get. Which sampling method is the fairest (least biased)?

• A. Post a poll that only night-owl gamers see
• B. Use a random number generator to pick students from every year group
• C. Ask students in the library at 8 am
• D. Ask your own class only