In a pack of 90 cards, each card was marked with a different number among 110 to 199. A card was selected at random. Find the probability that the number of it is not a perfect square.

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lemjay eNotes educator| Certified Educator

(Please disregard my previous posts.)

Take note that probability is a measure/estimate that an event is likely to happen. To compute, apply the formula:

 

               number of favorable outcomes

P(A) =  -------------------------------------------

             total number of possible outcomes 

 

From 110 to 199, there are a total of 90 numbers present (see attached). Among the numbers present, only four of them have perfect square factors. These are:

`11^2 = 121`

`12^2=144`

`13^2=169`

`14^2=196`

This means that there are 86 numbers that are not prefect squares.

So out of 90 possible outcomes, there are 86 favorable outcomes in getting a number that is not a perfect square.

Applying the formula above, it will yield:

`P(A)= 86/90=43/45`

Therefore, the probability that the number selected is not a perfect square is `43/45` .

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lemjay eNotes educator| Certified Educator

Take note that probability is a measure/estimate that an event is likely to happen. To compute, apply the formula:

 

               number of favorable outcomes

P(A) =  -------------------------------------------

             total number of possible outcomes 

 

From 110 to 199, there are a total of 90 numbers present (see attached). Among the numbers present, only three of them have perfect square factors. These are:

`11^2 = 121`

`12^2=144`

`13^2=169`

This means that there are 87 numbers that are not prefect squares.

So out of 90 possible outcomes, there are 87 favorable outcomes in getting a number that is not a perfect square.

Applying the formula above, it will yield:

`P(A) = 87/90 = 29/30`

Therefore, the probability that the number selected is not a perfect square is `29/30` .

lemjay eNotes educator| Certified Educator

I apologize, I was not able to attach the list of numbers from 110 to 119 in my first post.

I'll attach it in now.

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vmath | Student

Hi.... 

The formula to find probability of an event is 

P(E) = (number of favorable outcomes)/(total number of possible outcomes) 

Here, total number of possible outcomes = 90

number of favorable outcomes = 90 - 4 = 86 ( `11^2, 12^2, 13^2` and `14^2` )

 

`therefore P(E) = 86/90 = 43/45 `