Answer:
2/7 or 0.2857
Step-by-step explanation:
The expected time before the first bulb burns out (two bulbs working) is given by the inverse of the probability that a bulb will go out each day:
The expected time before the second bulb burns out (one bulb working), after the first bulb goes out, is given by the inverse of the probability that the second bulb will go out each day:
Therefore, the long-run fraction of time that there is exactly one bulb working is:
There is exactly one bulb working 2/7 or 0.2857 of the time.
Answer:
The five friends had 10 fingers to start with; one had two each
Step-by-step explanation:
The statement says each gave one of not all of his ginger in the toasting session.
Conditional probability is a measure of the probability of an event given that another event has occurred. If the event of interest is A and the event B is known or assumed to have occurred, "the conditional probability of A given B", or "the probability of A under the condition B", is usually written as P(A|B), or sometimes
.
The conditional probability of event A happening, given that event B has happened, written as P(A|B) is given by
In the question, we were told that there are three randomly selected coins which can be a nickel, a dime or a quarter.
The probability of selecting one coin is
Part A:
To find <span>the probability that all three coins are quarters if the first two envelopes Jeanne opens each contain a quarter, let the event that all three coins are quarters be A and the event that the first two envelopes Jeanne opens each contain a quarter be B.
P(A) means that the first envelope contains a quarter AND the second envelope contains a quarter AND the third envelope contains a quarter.
Thus
</span><span>P(B) means that the first envelope contains a quarter AND the
second envelope contains a quarter
</span><span>Thus
Therefore,
Part B:
</span>To find the probability that all three coins are different if the first envelope Jeanne opens contains a dime<span>, let the event that all three coins are different be C and the event that the first envelope Jeanne opens contains a dime be D.
</span><span>
</span><span>
</span><span>
Therefore,
</span>
Answer:
99.87% of the store’s total delivery orders will be delivered to consumers with charge
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
If a pizza store’s policy is, "Orders delivered within one hour or they’re free!", what percentage of the store’s total delivery orders will be delivered to consumers with charge?
Within one hour, which is 60 minutes. So this is the pvalue of Z when X = 60.
has a pvalue of 0.9987
99.87% of the store’s total delivery orders will be delivered to consumers with charge
Answer:
14
Step-by-step explanation:
Convert the fraction into a decimal
1/2 = 0.5
Divide
7/0.5 = 14
