Answer:
- P(≥1 working) = 0.9936
- She raises her odds of completing the exam without failure by a factor of 13.5, from 11.5 : 1 to 155.25 : 1.
Step-by-step explanation:
1. Assuming the failure is in the calculator, not the operator, and the failures are independent, the probability of finishing with at least one working calculator is the complement of the probability that both will fail. That is ...
... P(≥1 working) = 1 - P(both fail) = 1 - P(fail)² = 1 - (1 - 0.92)² = 0.9936
2. The odds in favor of finishing an exam starting with only one calculator are 0.92 : 0.08 = 11.5 : 1.
If two calculators are brought to the exam, the odds in favor of at least one working calculator are 0.9936 : 0.0064 = 155.25 : 1.
This odds ratio is 155.25/11.5 = 13.5 times as good as the odds with only one calculator.
_____
My assessment is that there is significant gain from bringing a backup. (Personally, I might investigate why the probability of failure is so high. I have not had such bad luck with calculators, which makes me wonder if operator error is involved.)
Answer:
The maximum revenue is $900, obtained with 30 people
Step-by-step explanation:
Naturally, the answer should be a number equal or higher than 20, because up to 20 persons, each one pays the same. Lets define a revenue function for x greater than or equal to 20.
f(x) = x*(40-(x-20)) = -x²+60x
Note that f multiplies the number of persons by how much would they pay (here, assuming that there are more than 20).
f is quadratic with negative main coefficient and its maximum value will be reached at the vertex.
The value of the x coordinate of the vertex is -b/2a = -60/-2 = 30
for x = 30, f(x) = 30*(40-(30-20))=30*30=900
So the maximum revenue is $900.
Answer:
Step-by-step explanation:
The Young's Module of Aluminium is 
. The axial stress on the specimen is:
The strain is derived of following expression:
Answer:
Step-by-step explanation:
we have
-----> equation A
-----> equation B
To find out (V of r)(t) substitute equation B in equation A
