Answer:
Randy had 13 books an Sandy had 7 books.
Step-by-step explanation:
20 - 3 = 17
30 - 17 = 13
13 x 2 = 26
26 + 4 = 30
13 + 7 = 20
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All of the above are true
Given that X <span>be the number of subjects who test positive for the disease out of the 30 healthy subjects used for the test.
The probability of success, i.e. the probability that a healthy subject tests positive is given as 2% = 0.02
Part A:
</span><span>The probability that all 30 subjects will appropriately test as not being infected, that is the probability that none of the healthy subjects will test positive is given by:
</span>

<span>
Part B:
The mean of a binomial distribution is given by
</span>

<span>
The standard deviation is given by:
</span>

<span>
Part C:
This test will not be a trusted test in the field of medicine as it has a standard deviation higher than the mean. The testing method will not be consistent in determining the infection of hepatitis.</span>
<em>x = 8</em>
Step-by-step explanation:

Add 1 to both sides.

Add 2x to both sides.

Divide 40 by 5.
x = 8