Answer:
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the lifetime for a TV of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability like this:
And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.
Answer: 58.016
Step-by-step explanation:
Answer:
divide it
Step-by-step explanation:
Tn=n/2^(n+1)
<span><span>t<span>n+1</span></span>=(n+1)/<span>2<span>n+2</span></span>=n/<span>2<span>n+2</span></span>+1/<span>2<span>n+2</span></span></span>
<span><span>t<span>n+1</span></span>=<span>tn</span>/2+1/<span>2<span>n+2</span></span></span>
t2=t1/2+1/2^3
t3=t2/2+1/2^4
.
.
.
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adding Sn-t1=Sn/2 +(1/2^3+1/2^4+.........)
Sn/2=t1+(1/2^3+1/2^4....)
Sn/2=1/4+(1/2^3)(1/(1-1/2))
=1/4+1/4
Sn=1