Random samples from a known group

Answer Key - Grade 8 Math Worksheet - Building Confidence

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

1. 1.

   5 blue dots and 7 yellow dots. Each sample is drawn without looking; return all counters before the next. Ari has a bag with 5 blue counters out of 12. Ari draws 4 random samples of 6, returning all counters each time. About how many blue draws would match the bag's makeup?

   10
2. 2.

   Each sample is drawn without looking; return all counters before the next. Bo has a bag with 3 blue counters out of 10. Bo draws 4 random samples of 5, returning all counters each time. About how many blue draws would match the bag's makeup?

   6
3. 3.

   4 blue dots and 6 yellow dots. Each sample is drawn without looking; return all counters before the next. Esme has a bag with 4 blue counters out of 10. Esme draws 5 random samples of 6, returning all counters each time. About how many blue draws would match the bag's makeup?

   12
4. 4.

   7 blue dots and 3 yellow dots. Each sample is drawn without looking; return all counters before the next. Kira has a bag with 7 blue counters out of 10. Kira draws 4 random samples of 5, returning all counters each time. About how many blue draws would match the bag's makeup?

   14
5. 5.

   7 blue dots and 5 yellow dots. Each sample is drawn without looking; return all counters before the next. Milo has a bag with 7 blue counters out of 12. Milo draws 4 random samples of 6, returning all counters each time. About how many blue draws would match the bag's makeup?

   14
6. 6.

   Each sample is drawn without looking; return all counters before the next. Noah has a bag with 3 blue counters out of 10. Noah draws 6 random samples of 5, returning all counters each time. About how many blue draws would match the bag's makeup?

   9
7. 7.

   4 blue dots and 6 yellow dots. Each sample is drawn without looking; return all counters before the next. Pia has a bag with 4 blue counters out of 10. Pia draws 6 random samples of 5, returning all counters each time. About how many blue draws would match the bag's makeup?

   12
8. 8.

   7 blue dots and 3 yellow dots. Each sample is drawn without looking; return all counters before the next. Tala has a bag with 7 blue counters out of 10. Tala draws 6 random samples of 5, returning all counters each time. About how many blue draws would match the bag's makeup?

   21
9. 9.

   Zee has a bag with 8 blue counters out of 10. Zee draws 6 random samples of 5, returning all counters each time. About how many blue draws would match the bag's makeup?

   24
10. 10.

    Jun draws four random samples of five counters from a known bag with 7 blue of 10. Which statement best describes how the samples represent the bag?

    • The samples differ, but their combined blue share is near the bag’s blue share.
    • Equal-size random samples must have the same blue count.
    • Different blue counts prove the drawing method was unfair.
    • Only the first sample tells us the bag’s blue share.