Does this sample fairly show the whole group?

Answer Key - Grade 7 Math Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. 1.

   Ari wants to learn about every tomato plant in the school bed but measures only 3 of them. One tomato plant leaned toward the camera. Which choice names the population, the whole group?

   • the heights in inches
   • all the tomato plants in town
   • the 3 tomato plants Ari measured
   • all 9 tomato plants in the school bed
2. 2.

   Luz wants to learn about every member of the piano club but measures only 3 of them. The piano was not available for comment. Which choice names the population, the whole group?

   • the 3 piano club members Luz measured
   • all the piano clubs in the county
   • all 8 members of the piano club
   • the minutes of practice a week
3. 3.

   Jun wants to learn about every pet snail in the science room but times only 3 of them. No snail was rushed. Which choice names the sample, the part that was picked?

   • the 3 pet snails Jun timed
   • all 8 pet snails in the science room
   • all the snails in the world
   • the centimeters crawled in a minute
4. 4.

   Picture each of the 240 students as one dot on a dot plot. The sample is the 8 dots picked. Pia wants to know how many minutes the 240 students at Maple School read each night, and can ask 8 students. Which way of choosing gives a sample that fairly shows all 240?

   • Ask the 8 students who sit closest to the classroom door.
   • Draw 8 names from a hat holding all 240 student names.
   • Ask the 8 students who belong to the school book club.
   • Ask the first 8 students who volunteer to answer.
5. 5.

   Picture each of the 150 students as one dot on a dot plot. The sample is the 10 dots picked. Bo wants to know how long the 150 seventh graders take to get to school, and can ask 10. Which way of choosing gives a sample that fairly shows all 150?

   • Ask the 10 students who live on Bo's street.
   • Ask the 10 students who ride bus number 4.
   • Ask the 10 students who sign up on a sheet.
   • Number all 150 students and pick 10 numbers at random.
6. 6.

   Picture each of the 200 players as one dot on a dot plot. The sample is the 10 dots picked. Zee wants to know how many minutes the 200 players in a school band practice each week, and can ask 10 players. Which way of choosing gives a sample that fairly shows all 200?

   • Ask the 10 players who sit in the first chairs.
   • Give every player a number and let a random-number tool pick 10.
   • Ask the 10 players who answer Zee's note.
   • Ask the 10 players who are in the band room right now.
7. 7.

   Kira measured all 8 sunflowers, then picked the 3 tallest. One leaned toward the camera. How far is the mean of the 3 picked from the mean of all 8?

   6.5
8. 8.

   Ren measured all 8 runners, then picked the 3 fastest. Nobody tripped over a shoelace. How far is the mean of the 3 picked from the mean of all 8?

   2
9. 9.

   Esme measured all 8 students, then picked 4 cards from a shuffled set of 8. The jump rope tangled itself. How far is the mean of the 4 picked from the mean of all 8?

   0.5
10. 10.

    Noah measured all 8 leaves, then picked 4 tags from a bag of 8. A squirrel supervised. How far is the mean of the 4 picked from the mean of all 8?

    0.5