M4maths Previous Puzzles

21 May 2010 Drop four Letters

There are four different letters and four different letter boxes, in how many methods these letters can be dropped in the boxes,
if all the four letters in a single box are not allowed:

OPtion

1) 250
2) 248
3) 256
4) 320
5) 252
6) 128
7) 224
8) 90
9) 4
10) 16

Solution

Total no. of methods without any condition = 4*4*4*4 = 256
No of methods of taking all the four letters in a box = 4
Hence required methods with given condition = 256-4 = 252

Correct Option: 5 Best Solution (4)

SUDESHNA SEN   15 years AGO

The first letter can be posted in any of the 4 letter boxes. Therefore, it has 4 choices.

Similarly, the second, the third and the fourth letter can each be posted in any of the 4 post boxes.

Therefore, the total number of ways the 4 letters can be posted in 4 letter boxes is 4*4*4*4
= 256.
Now all the 4 letters in a single box are not allowed.
This can happen in 4 ways.
Therfore, the required number of methods= 256-4= 252.....Option 5)

Like? Yes (1) | No   

Mamon Sengupta   15 years AGO

The first letter can be posted in any of the 4 letter boxes. Therefore, it has 4 choices.

Similarly, the second, the third and the fourth letter can each be posted in any of the 4 post boxes.

Therefore, the total number of ways the 4 letters can be posted in 4 letter boxes is 4*4*4*4
= 256.
Now all the 4 letters in a single box are not allowed.
This can happen in 4 ways.
Therfore, the required number of methods= 256-4= 252.....Option 5)

Like? Yes (1) | No   

Trishita Dasgupta   15 years AGO

The first letter can be posted in any of the 4 letter boxes. Therefore, it has 4 choices.

Similarly, the second, the third and the fourth letter can each be posted in any of the 4 post boxes.

Therefore, the total number of ways the 4 letters can be posted in 4 letter boxes is 4*4*4*4
= 256.
Now all the 4 letters in a single box are not allowed.
This can happen in 4 ways.
Therfore, the required number of methods= 256-4= 252.....Option 5)

Like? Yes (1) | No   

ASHOK ROY   15 years AGO

The first letter can be posted in any of the 4 letter boxes. Therefore, it has 4 choices.

Similarly, the second, the third and the fourth letter can each be posted in any of the 4 post boxes.

Therefore, the total number of ways the 4 letters can be posted in 4 letter boxes is 4*4*4*4
= 256.
Now all the 4 letters in a single box are not allowed.
This can happen in 4 ways.
Therfore, the required number of methods= 256-4= 252.....Option 5)

Like? Yes (1) | No