Question

There are 4 blue marbles,5 red marbles,1green marble and 2 black marbles in a bag.Suppose you select one marble at random.Find probability that : (a) marble is black (b) marble is blue (c) marble is not green ​

Answer 1

Answer:

Total 12

Step-by-step explanation:

2/12 = 1/6

your answer

Answer 2

Given,

A bag contains:

4 blue marbles

5 red marbles

1 green marble

2 black marbles

To find,

If a marble is selected at random, then, the probability that:

(a) marble is black

(b) marble is blue

(c) marble is not green

Solution,

We can simply solve this mathematical problem using the following process:

Mathematically,

The probability of occurrence of a favorable event = P (favorable event)

= (Total number of occurrence of the favorable event) / (Total number of occurrence of all possible events)

= (Total number of occurrence of the favorable event) / (Total number of trials)

Now, according to the question;

Total number of marbles in the bag

= 4 blue marbles + 5 red marbles + 1 green marble + 2 black marbles

= 12 marbles

PART - (a)

As per the given question;

The favorable event is that the selected marble is black.

So, the total number of occurrences of the favorable event = number of black marbles in the bag = 2

And, the total number of trials = total number of marbles in the bag = 12

So, the probability that the selected marble is black

= (Total number of occurrence of the favorable event) / (Total number of trials)

= (number of black marbles in the bag)/(total number of marbles in the bag)

= 2/12 = 1/6 = 0.167

PART - (b)

As per the given question;

The favorable event is that the selected marble is blue.

So, the total number of occurrences of the favorable event = number of blue marbles in the bag = 4

And, the total number of trials = total number of marbles in the bag = 12

So, the probability that the selected marble is blue

= (Total number of occurrence of the favorable event) / (Total number of trials)

= (number of blue marbles in the bag)/(total number of marbles in the bag)

= 4/12 = 1/3 = 0.33

PART - (c)

As per the given question;

The favorable event is that the selected marble is not green, that is, the selected marble is either blue or red, or black.

So, the total number of occurrences of the favorable event = (total number of marbles in the bag) - (number of green marbles in the bag) = 12-1 = 11

And, the total number of trials = total number of marbles in the bag = 12

So, the probability that the selected marble is not green in color

= (Total number of occurrence of the favorable event) / (Total number of trials)

= (number of non-green marbles in the bag)/(total number of marbles in the bag)

= 11/12 = 0.917

Hence, the probability that the selected marble is black, blue, and non-green, is equal to 0.167, 0.33, and 0.917, respectively.