The awnser is 145
(50 divided 2) = 25
5 to the power of 3= 125
-5
=145
Answer:
a. 0.047
b. Unlikely.
Step-by-step explanation:
a. The probability of a test result being wrong for a person not using mrijuana = 8 / 170 = 0.047.
b. As the probability for a wrong result is < 0.05 we can say that the test is unlikely to be wrong.
This is a combination in which you choose 4 from 10.
The formula is
combinations = 10! / 4! * (10-4)!
combinations = 10! / 4! * 6!
combinations = 10 * 9 * 8 * 7 * 6! / 4! * 6!
combinations = 10 * 9 * 8 * 7 / 4 * 3 * 2
combinations = 10 * 3 * 7
combinations = 210
Source:
http://www.1728.org/combinat.htm