Two-step chance: lists, tables and trees

Answer Key - Grade 7 Math Worksheet - Challenge Me

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

1. 1.

   Tala flips a fair coin three times. What is the chance of at least one head, in simplest form?

   7/8
2. 2.

   Zee rolls two fair number cubes. What is the chance of at least one 6, in simplest form?

   11/36
3. 3.

   Ari spins two spinners, each with 4 equal parts numbered 1 to 4. What is the chance of at least one 4, in simplest form?

   7/16
4. 4.

   Bo flips a fair coin four times (a tired thumb is expected). What is the chance of at least one tail, in simplest form?

   15/16
5. 5.

   A bag holds 5 different buttons. Jun draws one, keeps it out, then draws a second. How many outcomes are in the list of the two draws, with order counting?

   20
6. 6.

   Kira has 6 different star stickers and picks one, sets it aside, then picks a second. How many outcomes are in the list of the two picks, with order counting?

   30
7. 7.

   A bag holds 3 red buttons and 2 blue buttons. Milo draws one without looking, keeps it out, then draws a second. What is the chance both are red, in simplest form?

   3/10
8. 8.

   A bag holds 3 red buttons and 3 blue buttons. Noah draws one without looking, keeps it out, then draws a second. What is the chance both are blue, in simplest form?

   1/5
9. 9.

   Ren rolls a fair number cube and then flips a fair coin twice. How many outcomes are in the list for all three steps?

   24
10. 10.

    Zee spins two spinners, each with 5 equal parts numbered 1 to 5. What is the chance that the sum is 6, as a percent?

    20