Question

a dice is rolled thrree times and outcomes where the sum of three numbers apperaing on the uppermost face is 15 noted.the change that four appear on first dice is

Answer 1

Answer:

The sum of numbers can be 15 in the following three ways :

Case I: 15=3+6+6

The first, second and third throws can be (3,6,6),(6,3,6) and (6,6,3) respectively.

Total number of ways in which 3,6 and 6 can be obtained = 6

Case II: 15=4+5+6

The first, second and third throws can be  4, 5 and 6.

Total number of ways in which 4,5 and 6 can be obtained = 6

Case III: 15=5+5+5

The first, second and third throws can be 5,5 and 5.

Total number of ways in which 5,5, and 5 can be obtained = 1.

Hence, The total number of ways=3+6+1=10

The total number of ways in which the first roll will be 4 is 2.

Required chance = 2/10 = 1/5

Step-by-step explanation: