Three dice having digits 1, 2, 3, 4, 5 and 6 on their faces are marked I, II and III and rolled. Let x, y and z represent the number on die-I, die-II and die-III respectively. What is the number of possible outcomes such that x > y > z?
Three dice having digits 1, 2, 3, 4, 5 and 6 on their faces are marked I, II and III and rolled. Let x, y and z represent the number on die-I, die-II and die-III respectively. What is the number of possible outcomes such that x > y > z? Correct Answer 20
Calculation:
Let x, y and z represent the number on die-I, die-II and die-III respectively.
Given: x > y > z
It means the smaller number is shown on Die-III (z) than Die-II (y)
|
Possible cases |
Die-III (Z) |
Die-II (y) |
Die-I (x) |
Total No. of Ways |
|
I |
1 |
2 |
3, 4, 5, 6 |
4 |
|
3 |
4, 5, 6 |
3 |
||
|
4 |
5, 6 |
2 |
||
|
5 |
6 |
1 |
||
|
II |
2 |
3 |
4, 5, 6 |
3 |
|
4 |
5, 6 |
2 |
||
|
5 |
6 |
1 |
||
|
III |
3 |
4 |
5, 6 |
2 |
|
5 |
6 |
1 |
||
|
IV |
4 |
5 |
6 |
1 |
Total number of ways = 4 + 3 + 2 + 1 + 3 + 2 + 1 + 2 + 1 + 1 = 20
∴ Option 4 is correct.
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Feb 20, 2025

