Answer:
a) 0.0023
b) 0.007
c) 0.993
Step-by-step explanation:
The total number of marbles are;
5 + 10 = 15
Probability of red = 5/15
Probability of white = 8/15
Probability of 4 being red means, 4 will be white too;
Thus, the probability without replacement will be;
5/15 * 4/14 * 3/13 * 2/12 * 10/11 * 9/10 * 8/9 * 7/8 =
0.002331002331 which is approximately 0.0023
b. All white
Here, we have all the marbles selected being white
Thus the probability without replacement will be;
10/15 * 9/14 * 8/13 * 7/12 * 6/11 * 5/10 * 4/9 * 3/8
= 0.006993006993 which is approximately 0.007
c. At least one will be red
Mathematically, that will be;
1 - p(no red)
p(no red) = p(all white)
P(all white) = 0.007
hence P(no red) = 0.007
P(at least one red) = 1 - 0.007 = 0.993
