There are 7 black balls and 8 red balls in an urn. If 4 balls are drawn without replacement, what is the probability that exactly 1 black ball is drawn? Express your answer as a fraction or a decimal number rounded to four decimal places.

0.0718

Step-by-step explanation:

Given that there are 7 black balls and 8 red balls.

Probability of an event E is given as:

The required probability that exactly one black ball is drawn out of 4 drawn balls = Probability of drawing 1 black ball Probability of drawing 3 black balls.

First of all, let us see the probability of drawing one black ball:

Number of favorable cases = 7 (Total number of black balls)

Total number of cases = 15 (Total number of black balls and red balls)

Now, have a look at probability of choosing 3 red balls:

We have to choose 3 red balls out of 8 balls:

Total number of favorable cases = = 8

Now, one black ball is already chosen, so total 14 balls are left out of which 3 balls are to be chosen.

So, total number of cases =

The required probability =

So, the required probability is 0.0718.

circle area = pi * radius^2

if diameter = 10 then radius = 5

circle area = pi * 5^2

circle area = pi * 25

circle area = 78.5398163397 square units

step-by-step explanation:

answer is 12345678900987654321234567890987654321

step-by-step explanation: