Find the indicated probability. Round to the nearest thousandth.
-In a blood testing procedure, blood samples from 6 people are combined into one mixture. The mixture will only test negative if all the individual samples are negative. If the probability that an individual sample tests
Positive is 0.1, what is the probability that the mixture will test positive?
A) 1.00
B) 0.531
C) 0.00000100
D) 0.469

Question

Quizplus · Accepted Answer

The probability of an individual sample testing negative is 0.9 (since there are only two possible outcomes, positive and negative, and the probabilities must add up to 1). Therefore, the probability that all 6 samples test negative is: 
0.9 x 0.9 x 0.9 x 0.9 x 0.9 x 0.9 = 0.531441
This means that the probability of the mixture testing positive (at least one sample tests positive) is:
1 - 0.531441 = 0.468559
Rounding to the nearest thousandth gives the answer D: 0.469.

Find the Indicated Probability