# Question #81855

##### 2 Answers

P(divisible by 5)

#### Explanation:

Total no. Of outcomes= 6*4

= 24

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alternate derivation:

There are 4 choice for the first digit;

for each of these there are 3 choices for the second digit;

for each of these there are 2 choices for the third digit;

leaving only 1 possibility for the fourth digit.

Total number of ways of composing a 4-digit number

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Outcomes where divisibility by 5 is possible = 6

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explanation of derivation:

To be divisible by 5 the last digit must be 5;

this leaves 3 choices for the first digit;

2 choices for the second digit; and

1 possibility left for the last digit.

Number of ways of composing 4-digit number ending in 5:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Hence probability of getting a no. which is divisible by 5 = 6/24 = 1/4

Probability =1/4

The probability is

#### Explanation:

The probability can be calculated by dividing the number of outcomes fulfilling the condition by the total number of outcomes:

#P(A)=(bar(bar(A)))/bar(bar(Omega))#

Here the number of all outcomes can be calculated as:

The condition for outcomes in *the number is divisible by 5*, so its last digit has to be

The remaining 3 digits can be arranges in

Now we can calculate the probability:

#P(A)=4/24=1/4=0.25#

Original answer:

Probability = Favorable outcome / Total outcome

Outcomes= 1253 1235 1523 1532 1352 1325 2135 2153 2351 2315 2513 2531 3512 3521 3125 3215 3152 3251

Total number of outcomes= 18

Favorable outcomes=1235 1325 2135 2315 3125 3215

Number of favorable outcome= 6

Probability= Favorable outcome / Total outcome

```
= #6/18#
= 3
```