Solution
Understanding the set :-
- This set tells us about a game called Hi - Lo, having 6 rounds.
- Rules for game :-
a) In every round, each player chooses to bid Hi or Lo
b) Let 'H' represents Hi and 'L' represents Lo.
Given if they bid
Case 1: HHHH then all players gets -1 points.
Case 2: HHHL => H gets +1 and L gets -3.
Case 3: HHLL => H gets +2 and L gets -2.
Case 4: HLLL => H gets +3 and L gets -1.
Case 5: LLLL => every player gets +1.
This is a game sand tournament + table set.
Most important thing in games and tournament sets is to read and understand rules of the game clearly.
Maybe you can jot down the rules as a short note in the corner of the paper.
| R1 | R2 | R3 | T1 | R4 | R5 | R6 | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 6 | 7 | ||||||
| B | -2 | -1 | ||||||
| C | -2 | -5 | ||||||
| D | 2 | -1 |
Here T1 = total of score till round 3
and, T2 = total of scores till round 6.
And, A, B, C, D are Arun, Bankim, Charu, and Dipak respectively.
| R1 | R2 | R3 | T1 | R4 | R5 | R6 | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 6 | 7 | ||||||
| B | -2 | -1 | ||||||
| C | -2 | -5 | ||||||
| D | x | y | z | 2 | -1 |
Clue 3 says,
Dipak’s score in the third round was less than his score in the first round but was more than his score in the second round.
Let Dipak's score in round 1 = x
in round 2 = y
and round 3 = z
=> y < z < x
| R1 | R2 | R3 | T1 | R4 | R5 | R6 | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2 | 3 | 1 | 6 | 7 | |||
| B | -2 | -1 | ||||||
| C | -2 | -5 | ||||||
| D | 2 | -1 | 1 | 2 | -1 |
Now, we know that D has scored a total of 2 from the first three rounds.
So, we can consider three possible cases for the values of x, y, and z:
Case - 1 : (x, y, z) = (3, -3, 2)
In this case the points of A in R1, R3, R2 will be in any possible combination the sum will not be 6.
So, this case is invalid.
Case - 2 : (x, y, z) = (2, -1, 1)
In this case the points of A in R1, R3, R2 will be
so, if the points in R1, R3, R2 are
Therefore, the case is valid and no other cases are possible.
Case - 3 : (x, y, z) = (3, -2, 1)
In this case the points of A in R1, R3, R2 will be in any possible combination the sum will not be 6.
So, this case is invalid.
.'. Points of A,D in (R1,R2,R3) are (2,3,1) and (2,-1,1) respectively.
| R1 | R2 | R3 | T1 | R4 | R5 | R6 | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2 | 3 - Hi | 1 | 6 | 7 | |||
| B | -1 - Lo | -2 | -1 | |||||
| C | -1 - Lo | -2 | -5 | |||||
| D | 2 | -1- Lo | 1 | 2 | -1 |
Since A got +3 in R2,
=> he is only the one to bid Hi in R2
and points of B and C in round 2 are
=> they bid Lo, Lo.
| R1 | R2 | R3 | T1 | R4 | R5 | R6 | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2- Hi | 3 - Hi | 1 | 6 | 7 | |||
| B | -2 - Lo | -1 - Lo | -2 | -1 | ||||
| C | -2 - Lo | -1 - Lo | -2 | -5 | ||||
| D | 2 - Hi | -1- Lo | 1 | 2 | -1 |
Since A and D got 2 points each in R1,
=> C and B must have got -2, -2
i.e they bid Lo, Lo.
| R1 | R2 | R3 | T1 | R4 | R5 | R6 | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2- Hi | 3 - Hi | 1 - Lo | 6 | 7 | |||
| B | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 | |||
| C | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -5 | |||
| D | 2 - Hi | -1- Lo | 1 - Lo | 2 | -1 |
Also, Since A and D got 1 point in R3,
=> C and B must also have got 1 in R3
i.e they bid Lo, Lo.
| R1 | R2 | R3 | T1 | R4 | R5 | R6 | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2- Hi | 3 - Hi | 1 - Lo | 6 | 7 | |||
| B | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 | |||
| C | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -5 | |||
| D | 2 - Hi | -1- Lo | 1 - Lo | 2 | -1 |
Now, we know,
-
for A - R1 + R2 + R3 = 1
-
For B - R1 + R2 + R3 = 1
-
For C - R1 + R2 + R3 = -3
-
For D - R1 + R2 + R3 = -3
| R1 | R2 | R3 | T1 | Rx | Ry | Rz | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2- Hi | 3 - Hi | 1 - Lo | 6 | 3 - Hi | 7 | ||
| B | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | -1 | ||
| C | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | -5 | ||
| D | 2 - Hi | -1- Lo | 1 - Lo | 2 | -1 - Lo | -1 |
Clue 4 says,
In exactly two out of the six rounds, Arun was the only player who bid Hi.
Let A bid Hi in R.x
(Here Rx is any of round 4, 5, or 6 - as we do not know the exact information of these three rounds)
=> B,C,D bid Lo.
| R1 | R2 | R3 | T1 | Rx | Ry | Rz | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2- Hi | 3 - Hi | 1 - Lo | 6 | 3 - Hi | 7 | ||
| B | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | -1 | ||
| C | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | -5 | ||
| D | 2 - Hi | -1- Lo | 1 - Lo | 2 | -1 - Lo | -1 |
For A,
R.x + R.y + R.z = 1
=> R.y + R.z = -2
For B,
R.x + R.y + R.z = 1
=> R.y + R.z = 2
For C,
R.x + R.y + R.z = -3
=> R.y + R.z = -2
For D,
R.x + R.y + R.z = -3.
=> R.y + R.z = -2
Therefore, (R.y, R.z) for A can be (-3,1) or (-1,-1).
| R1 | R2 | R3 | T1 | Rx | Ry | Rz | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2- Hi | 3 - Hi | 1 - Lo | 6 | 3 - Hi | 7 | ||
| B | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | -1 | ||
| C | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | -5 | ||
| D | 2 - Hi | -1- Lo | 1 - Lo | 2 | -1 - Lo | -1 |
Case - 1 :
If for A, (R.y, R.z)=(-3,1)
Since for both C,D: R.y+R.z=-2
We can't get any combination such that the total points of B,C,D are obtained.
| R1 | R2 | R3 | T1 | Rx | Ry | Rz | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2- Hi | 3 - Hi | 1 - Lo | 6 | 3 - Hi | -1 - Lo | -1 - Hi | 7 |
| B | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | 3 - Hi | -1 - Hi | -1 |
| C | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | -1- Lo | -1- Hi | -5 |
| D | 2 - Hi | -1- Lo | 1 - Lo | 2 | -1 - Lo | -1 - Lo | -1 - Hi | -1 |
Case - 2:
If for A, (R.y, R.z)=(-1,-1).
the (R.y, R.z) of B,C,D can be (3,-1), (-1,-1), (-1,-1)
and they must have bid (H,H), (L,H), (L,H) respectively
while A must have bid (L, H)
Hence this case is valid.
| R1 | R2 | R3 | T1 | Rx | Ry | Rz | T2 | |
|---|---|---|---|---|---|---|---|---|
| A | 2- Hi | 3 - Hi | 1 - Lo | 6 | 3 - Hi | -1 - Lo | -1 - Hi | 7 |
| B | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | 3 - Hi | -1 - Hi | -1 |
| C | -2 - Lo | -1 - Lo | 1 - Lo | -2 | -1 - Lo | -1- Lo | -1- Hi | -5 |
| D | 2 - Hi | -1- Lo | 1 - Lo | 2 | -1 - Lo | -1 - Lo | -1 - Hi | -1 |
R1 is the only round we are sure about Arun being the only player to bid Hi so answer is 1st option.
More from this set:
Question 6
Question 7