Solution
Understanding the set :-
- We are given nine boxes arranged in a 3×3 array - in the same way as shown in tables, in the question.
- There are 3 sacks in each box as well , which implies we need to find three numbers for a particular box.
- The average number of coins per sack in the boxes are all distinct integers, which means average of each box will be a distinct integer from 1 to 9
- The total number of coins in each row is the same. The total number of coins in each column is also the same.
- Also, question gives 2 tables where,
Table 1 - gives median of number of coins in a box
Table 2 - gives a number which represents the number of sacks in that box having more than 5 coins.
In this question we will try to find the number on each sack of each box.
Let us represent the final configuration of the sacks in boxes as follows:
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 45 | |||
| 2nd row | 45 | |||
| 3rd row | 45 | |||
| Total | 45 | 45 | 45 | 135 |
We know the average of all the boxes is a distinct integer from 1 to 9
Therefore, the total of all averages = 1+2+3+4+5+6+7+8+9 = 45
Also, we know The total number of coins in each row is the same. The total number of coins in each column is also the same
=> Sum of averages coins in a box in a row or column = 45/3 = 15
Since there are 3 rows and 3 columns the total of each one will come out to be 15 * 3 = 45
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 45 | |||
| 2nd row | 45 | |||
| 3rd row | 7, 8, 9 (8) | 45 | ||
| Total | 45 | 45 | 45 | 135 |
Consider bag (3,1) {3dr row and 1st column}
=> From Table-1 => Median = 8
From Table-2 - all 3 sacks have more than 5 coins
Also * - which implies the sacks in that box satisfy exactly one among the three conditions given in the question.
But we know minimum can't be 1 (as all 3 sacks have more then 3 coins)
also, Median of 3 sacks is not equal to 1
=> it follows 3rd condition
=> There is a 9 in one of the sacks.
=> c, 8, 9 are the coins in bag (3,1)
now c > 5 & c + 8 + 9 should be a multiple of 3
=> c = 7 is the only possibility. with average = 8
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 45 | |||
| 2nd row | 1, 2, 9 (4) | 45 | ||
| 3rd row | 7, 8, 9 (8) | 45 | ||
| Total | 45 | 45 | 45 | 135 |
Consider bag (2,1)
-
Median = 2
-
1 sack has more than 5 coins
-
Also ** => conditions i & iii should be satisfied.
=> 1, 2, 9 are the coins in bag (2,1). with average = 4
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 3, 9, 9 (7) | 45 | ||
| 2nd row | 1, 2, 9 (4) | 45 | ||
| 3rd row | 7, 8, 9 (8) | 45 | ||
| Total | 45 | 45 | 45 | 135 |
Consider bag (1,2)
-
Median = 9
-
2 elements are more than 5.
-
Also * => (9 is present & 1 is not present)
=> c, 9, 9 are the coins in bag (1,2)
and c is not equal to 1 and less than 5
=> c = 3 for c + 18 to be a multiple of 3.
=> 3, 9, 9 are the coins in bag (1,2) with average =7
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 1, 1, 7 (3) | 3, 9, 9 (7) | 45 | |
| 2nd row | 1, 2, 9 (4) | 45 | ||
| 3rd row | 7, 8, 9 (8) | 45 | ||
| Total | 45 | 45 | 45 | 135 |
Consider bag (1,1)
- Avg = 3
sum of average of each row = 15, and we already have (2, 1) average = 4 and (3, 1) average = 8
=> average of (1,1) = 3
- 1 sack has more than 5
- ** => 2 conditions are being satisfied.
condition 3 won't be fulfilled as average = 3
therefore, total in itself = 9
1, 1, 7 coins with average = 3
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 1, 1, 7 (3) | 3, 9, 9 (7) | 1, 6, 8 (5) | 45 |
| 2nd row | 1, 2, 9 (4) | 45 | ||
| 3rd row | 7, 8, 9 (8) | 45 | ||
| Total | 45 | 45 | 45 | 135 |
Consider bag (1,3)
- Avg. = 5 => Sum = 15.
As we know average of total= 15 and we already found average of (1,1) = 3 and (1,2) = 7
therefore, average of (1,3) = 15 - 3 - 7 = 5
- Median = 6 and 2 sacks have more than 5
-
- => (1 condition is satisfied)
Not condition ii as the median is 6
Not condition iii as the sum of 2 sacks itself will become 6 + 9 = 15
=> 1, 6, c are the coins
=> For sum = 15 => c = 15 - 1 - 6 = 8
=> bag (1,3) has 1, 6, 8 coins with average = 5
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 1, 1, 7 (3) | 3, 9, 9 (7) | 1, 6, 8 (5) | 45 |
| 2nd row | 1, 2, 9 (4) | 45 | ||
| 3rd row | 7, 8, 9 (8) | 1, 1, 1 (1) | 45 | |
| Total | 45 | 45 | 45 | 135 |
Consider bag (3,3)
- 0 sacks have more than 5 coins
- ** => conditions i & ii are being satisfied.
=> 1,1,c are the coins.
Now c = 1 or 2 or 3 or 4
=> c = 1 or 4 for number of coins to be a multiple of 3
But c will be 1
as no other bag has the possibility to get avg. = 1
=> bag (3,3) has 1, 1, 1 coins with average = 1
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 1, 1, 7 (3) | 3, 9, 9 (7) | 1, 6, 8 (5) | 45 |
| 2nd row | 1, 2, 9 (4) | 9, 9, 9 (9) | 45 | |
| 3rd row | 7, 8, 9 (8) | 1, 1, 1 (1) | 45 | |
| Total | 45 | 45 | 45 | 135 |
In bag (2,3)
Avg. = 9
=> 9, 9, 9 are the coins.
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 1, 1, 7 (3) | 3, 9, 9 (7) | 1, 6, 8 (5) | 45 |
| 2nd row | 1, 2, 9 (4) | 1, 2, 3 (2) | 9, 9, 9 (9) | 45 |
| 3rd row | 7, 8, 9 (8) | 1, 1, 1 (1) | 45 | |
| Total | 45 | 45 | 45 | 135 |
In bag (2,2)
- Avg. = 2
- Sum = 6
- 1* => smallest element hould be 1.
=> 1, b, c are the coins
=> b + c = 5 and b,c can't be equal to 1 and less than 5
=> 2 + 3 = 5 is the only possibility
=> 1, 2, 3 are the coins with average = 2
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 1, 1, 7 (3) | 3, 9, 9 (7) | 1, 6, 8 (5) | 45 |
| 2nd row | 1, 2, 9 (4) | 1, 2, 3 (2) | 9, 9, 9 (9) | 45 |
| 3rd row | 7, 8, 9 (8) | 1, 8, 9 (6) | 1, 1, 1 (1) | 45 |
| Total | 45 | 45 | 45 | 135 |
Considering bag (3,2)
1)Avg. = 6 => Sum = 18.
- 2 sacks more than 5 coins
- ** => 2 sacks have 1 and 9 coins.
=> bag (3,2) has 1, c, 9 coins and c = 18 - 1 - 9 = 8
=> bag (3,2) has 1, 8, 9 coins with average = 6 coins
| 1st column | 2nd column | 3rd column | Total | |
|---|---|---|---|---|
| 1st row | 1, 1, 7 (3) | 3, 9, 9 (7) | 1, 6, 8 (5) | 45 |
| 2nd row | 1, 2, 9 (4) | 1, 2, 3 (2) | 9, 9, 9 (9) | 45 |
| 3rd row | 7, 8, 9 (8) | 1, 8, 9 (6) | 1, 1, 1 (1) | 45 |
| Total | 45 | 45 | 45 | 135 |
for 4 boxes median and average will be same