Two-step chance: lists, tables and trees

Answer Key - Grade 7 Math Worksheet

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

1. 1.

   Bo flips a fair coin and spins a spinner with 6 equal parts numbered 1 to 6. What is the chance of heads and a 6, in simplest form?

   1/12
2. 2.

   Jun spins a spinner with 3 equal parts (red, blue, yellow) and draws a card from 1 to 5 without looking. What is the chance of blue and an odd card, in simplest form?

   1/5
3. 3.

   Luz flips a fair coin and spins a spinner with 4 equal parts numbered 1 to 4. What is the chance of heads and a 4, as a percent?

   12.5
4. 4.

   Pia rolls two fair number cubes. What is the chance that the sum is 7, in simplest form?

   1/6
5. 5.

   Zee rolls two fair number cubes. What is the chance that the sum is 6, in simplest form?

   5/36
6. 6.

   Ari flips two fair coins. What is the chance of exactly one head, in simplest form?

   1/2
7. 7.

   Esme spins two spinners, each with 4 equal parts: red, blue, green, yellow. What is the chance that the two colors are different, in simplest form?

   3/4
8. 8.

   Jun flips a fair coin three times. Which is the whole list of outcomes for the three flips?

   • HHH, HHT, HTH, HTT, THH, THT, TTH, TTT
   • HHH, HHT, HTH, HTT, THH, THT, TTH, with TTT left out
   • HHH, TTT
   • HHH, HHT, HTT, TTT
9. 9.

   Luz flips a fair coin and spins a spinner with 4 equal parts numbered 1 to 4. Which is the whole list of outcomes for both?

   • H1, H2, H3, H4
   • H, T, 1, 2, 3, 4
   • H1, H2, H3, H4, T1, T2, T3, T4, T5
   • H1, H2, H3, H4, T1, T2, T3, T4

10. Read this first

    Tree

    The card splits into red and blue; each of those splits into 1, 2, 3 and 4. Leaves: red-1, red-2, red-3, red-4, blue-1, blue-2, blue-3, blue-4.

11. 10.

    Pia picks 1 of 2 cards (1 red, 1 blue) without looking, then spins a spinner (1 to 4, equal parts). What is the chance of blue and a number over 2, in simplest form?

    1/4