Answer:
Option (b) 36.7
Step-by-step explanation:
Data provided in the question:
Treatment 1 Treatment 2 Treatment 3 Treatment 4
Sample Size 50 18 10 17
Sample Mean 32 36 42 48
Now,
The overall mean is calculated as
=
Here, Xi = Sample mean
n = sample sizes
Thus,
Overall mean
= [ (50 × 32) + (18 × 36) + (10 × 42) + (17 × 48) ] ÷ [ 50 + 18 + 10 + 17 ]
= [ 1600 + 648 + 420 + 816 ] ÷ 95
= 36.67 ≈ 36.7
hence,
Option (b) 36.7
Answer:
26.95% probability that at least one of them is cleared with an arrest
Step-by-step explanation:
For each burglary, there are only two possible outcomes. Either it is cleared, or it is not. The probability of a burglary being cleared is independent of other burglaries. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
In which is the number of different combinations of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
5.1% of burglaries are cleared with arrests.
This means that
A new detective is assigned to six different burglaries.
This means that
What is the probability that at least one of them is cleared with an arrest?
Either none are cleared, or at least one is. The sum of the probabilities of these events is 100% = 1. So
We want
Then
In which
26.95% probability that at least one of them is cleared with an arrest