College

A bag contains 9 white counters, 8 black counters, and 6 green counters.

What is the probability of drawing:

(a) a white counter or a green counter?

(b) a black counter or a green counter?

(c) not a green counter?

Answer :

In order to determine the probability fr each case, it is necessary to calculate the quotient between the number of desired cases and the total number of options.

a) a white counter or a green counter

Consider that there are 9 white counters and 6 green counters, that is, there are 9 + 6 = 15 counters with some characteristic you want.

The total number of counters are 9 + 8 + 6 = 23 counters. Then, the probability is:

P = 15/23 it is not possible to simplify the fractions

b) a black counter or a green counter

There are 8 black counters and 6 green counters, that is, 8 + 6 = 14 counters.

The probability is:

P = 14/23 it is not possible to simplify the fraction

c) not a green counter

It means only white and black counter. Then, there are 9 + 8 = 17 counters with a desired characteristic. The probability is:

P = 17/23

Final answer:

The probability of drawing a white counter or a green counter is 15 / 23. The probability of drawing a black counter or a green counter is 14 / 23. The probability of not drawing a green counter is 17 / 23.

Explanation:

To find the probability of drawing a white counter or a green counter, we need to find the sum of their probabilities and subtract the probability of drawing both.

(a) Probability of drawing a white counter = Number of white counters / Total number of counters = 9 / 23.

Probability of drawing a green counter = Number of green counters / Total number of counters = 6 / 23.

The probability of drawing both a white counter and a green counter = 0 (since they are mutually exclusive colors).

So, the probability of drawing a white counter or a green counter = Probability of drawing a white counter + Probability of drawing a green counter - Probability of drawing both = 9 / 23 + 6 / 23 - 0 = 15 / 23.

(b) Similarly, the probability of drawing a black counter or a green counter can be calculated as follows: Probability of drawing a black counter = Number of black counters / Total number of counters = 8 / 23.

So, the probability of drawing a black counter or a green counter = Probability of drawing a black counter + Probability of drawing a green counter - Probability of drawing both = 8 / 23 + 6 / 23 - 0 = 14 / 23.

(c) The probability of not drawing a green counter can be calculated as 1 - Probability of drawing a green counter = 1 - 6 / 23 = 17 / 23.