Answer:
Lower limit: 113.28
Upper limit: 126.72
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:

Middle 60%
So it goes from X when Z has a pvalue of 0.5 - 0.6/2 = 0.2 to X when Z has a pvalue of 0.5 + 0.6/2 = 0.8
Lower limit
X when Z has a pvalue of 0.20. So X when 




Upper limit
X when Z has a pvalue of 0.80. So X when 




Answer:
99
Step-by-step explanation:
99 x 33 x 3 can be simplified to 99 x 99. If you square root this you will end up with 99
This is equal to the probability that no light fail. Probability of one light not failing = 0.98.
P(no light fails) = 0.98^20 = 0.67 or 67% to nearest percent.
I'm guessing the diagram shows a ladder leaning against a wall, making a right angle triangle with respect to the ground and the wall.
So, the wall's height is going to be the 'h', which will also be the 'opposite side' from the angle <span>ϴ which is made from the ladder and the ground.
</span>The ladder's length (18 foot) is going to be the 'hypotenuse' side and the other remaining side will be the 'adjacent'.
Now, once you've sorted out which side is which, we have to find the h (opp), and according to SOH CAH TOA, we will choose Sin<span>ϴ = opp/hyp.
</span>so Sinϴ = h/18....now we gotta find h, so 'cross multiply' the equation to get h = 18 x sin<span>ϴ.
</span>
To find angle ϴ, simply take the inverse of Sinϴ= h/18... and you'll get ϴ = sin-1 (sin inverse) h/18
Hope this helps