Question

There are 10 counters in a bag: 3 are red, 2 are blue and 5 are green. The contents of the bag are shaken before maxine randomly chooses one counter from the bag. What is the probability that she doesn't pick a red counter?

Answer 1

Answer:

total number of counters = 10

number of red counters= 3

number of blue counters= 2

number of green counters = 5

p(of getting a red counter) =3/10

p(of not getting a red counter) = 1-3/10= 10-3/10=7/10

Answer 2

Given,

There are 10 counters in a bag: 3 are red, 2 are blue and 5 are green.

The contents of the bag are shaken before maxine randomly chooses one counter from the bag.

To find,

The probability that she doesn't pick a red counter.

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)

As per the given question;

The favorable event is the occurrence of any counter other than red, which is the occurrence of a blue or green counter.

So, the frequency of occurrence of the favorable event = (number of blue counters) + (number of green counters) = 2 + 5 = 7

And, the total number of trials = total number of counters on the bag = 10

So, the probability that she doesn't pick a red counter

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

= (frequency of occurrence of the favorable event)/(total number of counters on the bag)

= 7/10 = 0.7

Hence, the probability that she doesn't pick a red counter is equal to 0.7.