Chance of two events in a row

Answer Key - Grade 8 Math Worksheet - Building Confidence

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

1. 1.

   Ari flips a fair coin and spins a spinner with 3 equal parts (red, blue, yellow). Heads has chance 1/2; red has chance 1/3. What is the chance of heads and red?

   1/6
2. 2.

   Esme's bag has 2 red and 3 blue marbles. Esme draws one without looking. It is put back, and Esme draws again. Red has chance 2/5 each time. What is the chance both are red?

   4/25
3. 3.

   Jun's bag has 3 red and 5 blue marbles. Jun draws two without looking. The first is not put back. Which product gives the chance both are red?

   • 3/8 + 2/7
   • 3/8 × 3/8
   • 3/8 × 2/7
4. 4.

   Kira's bag has 4 green and 2 yellow marbles. Kira draws one without looking. It is put back, and Kira draws again. Which product gives the chance both are green?

   • 4/6 × 4/6
   • 4/6 + 4/6
   • 4/6 × 3/5
5. 5.

   Luz puts cards numbered 1 to 5 in a hat. Luz draws two without looking, and the first is not put back. Which product gives the chance both are odd?

   • 3/5 × 2/4
   • 3/5 × 3/4
   • 3/5 × 3/5
6. 6.

   Milo spins a spinner with 2 equal parts, red and blue, and rolls a fair number cube. What is the chance of red and a number less than 3, in simplest form?

   1/6
7. 7.

   Noah's bag has 1 red and 3 blue marbles. Noah draws one without looking. It is put back, and Noah draws again. What is the chance both are blue, in simplest form?

   9/16
8. 8.

   Pia's spinner has 5 equal parts, and 2 of them are stars. Pia spins it and flips a fair coin. What is the chance of a star and heads, in simplest form?

   1/5
9. 9.

   Ren's bag has 2 red and 4 blue marbles. Ren draws two without looking, and the first is not put back. What is the chance both are blue, in simplest form?

   2/5
10. 10.

    Tala draws two of 5 names from a hat without looking, and the first is not put back. Zee's name is in the hat. What is the chance of Tala's name, then Zee's?

    1/20