Answer: 2/3
Step-by-step explanation: In this problem, we have 8/15 ÷ 4/5. Dividing by a fraction is the same as multiplying by its reciprocal. In other words, we can change the division sign to multiplication and flip the second fraction.
8/15 ÷ 4/5 can be rewritten as 8/15 × 5/4
Now, we are simply multiplying fractions so we multiply across the numerators and multiply across the denominators.
8/15 × 5/4 = 40/60 = 2/3
Answer:
0 tests
Yes, this procedure is better on the average than testing everyone, it makes it less cumbersome.
Step-by-step explanation:
Given the information:
Let P be the probability that a randomly selected individual has the disease = 0.1. N individuals are randomly selected, thereafter, blood samples of each person would be tested after combining all specimens. Should in case one person has the disease then it yields a positive result and test should be set for each person.
Let Y be number tests
For n = 3 there are two possibilities. If no one has the disease then the value is 1 otherwise the value is 4, here P = 0.1
Therefore, for Y = 1
P(Y-1) = P(no one has disease)
= 0.9³
= 0.729
If Y = 4
P(Y-4) = 1-P(y = 1)
= 1 - 0.729 = 0.271
The expected number of tests using this formular gives
E(Y) = 1×0.729 + 4×0.271
E(Y) = 0
See attached picture for answer
Step-by-step explanation:
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Welcome
Answer:
30
Step-by-step explanation:
i had the same test xD
