Sum Probability

Solution

Anna has Card 7.
Daisy has Card 3.
Jeff has Card 11.
Russ has Card 4.

Explanation

Step 1

Find out how many combinations there are for each card.
Make a list.

  3 4 7 11
Possible combinations 1 + 2
2 + 1
1 + 3
3 + 1
2 + 2
3 + 4
4 + 3
5 + 2
2 + 5
1 + 6
6 + 1
5 + 6
6 + 5
Total number of combinations 2 3 6 2

Step 2

Find out the total number of possible outcomes using 2 cubes.
6 x 6 = 36
There are 36 possible combinations.

Step 3

Find out the probability of getting each one of the numbers on the cards.
Use a ratio to find each probability.

combinations possible for each card =   outcomes in event
36 possible outcomes

 

  3 4 7 11
Probability two-thirty-sixths three-thirty-sixths six-thirty-sixths two-thirty-sixths

Step 4

Use the clues.

  • Anna has the greatest probability of scoring a point on her first turn. She must have Card 7 because it has the probability of 6 out of 36.
  • Jeff's and Daisy's cards have the same probability. They must have Cards 3 and 11 because the probability of scoring a point with those cards is 2 out of 36.
  • Jeff's card has a higher number than Daisy's. He must have Card 11.
  • The probability of Russ earning a point is greater than that of Jeff earning a point. He must have Card 4 because the probability of that card is 3 out of 36.

Summary

Anna has Card 7.
Daisy has Card 3.
Jeff has Card 11.
Russ has Card 4.



Houghton Mifflin Math Grade 6