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Science-Related Homework Help Statistics and Probability Topic started by: anhsu on Aug 30, 2019



Title: Grades You believe that there is a 20% chance that you will earn an A in your English class, a 10% ...
Post by: anhsu on Aug 30, 2019
Grades You believe that there is a 20% chance that you will earn an A in your English class, a 10% chance that you will earn an A in your Physics class, and a 5% chance that you will earn an A in both classes.

a. Find the probability that you do not get an A in either English or Physics.
b. Are "earning an A in English" and "earning an A in Physics" disjoint events? Explain.
c. Are "earning an A in English" and "'earning an A in Physics" independent events? Explain.


Title: Grades You believe that there is a 20% chance that you will earn an A in your English class, a 10% ...
Post by: mace on Aug 30, 2019
a. Let E = earn an A in English and Ph = earn an A in Physics.
    P(not E and not Ph) = 1 - P(E or Ph) = 1- [0.20 + 0.10 - 0.05] = 1 - 0.25 = 0.75
b. These are not disjoint events since she can earn an A in English and an A in Physics.
c. P(Ph) = = 0.25 ≠ 0.10 =  P(Ph) , so these events are not independent.


Title: Grades You believe that there is a 20% chance that you will earn an A in your English class, a 10% ...
Post by: anhsu on Aug 30, 2019
TY


Title: Grades You believe that there is a 20% chance that you will earn an A in your English class, a 10% ...
Post by: mace on Aug 30, 2019
Welcome :)