A teacher designs a test so a student who studies will pass 90% of the time, but a student who does not study will pass 11% of the time. A certain student studies for 85% of the tests taken. On a given test, what is the probability that student passes?

Using the percentages given, it is found that there is a 0.7815 = 78.15% probability that student passes.

The percentages associated with passing the test are given by:

Hence, adding these percentages:

0.7815 x 100% = 78.15%

There is a 0.7815 = 78.15% probability that student passes.

A similar problem, also involving the use of percentages, is given at link

probability that student passes = 0.7815

Step-by-step explanation:

Given:

Student studies = 85% = 0.85

Student not study = 11% = 0.11

Student who pass = 90% = 0.90

Computation:

P(student not pass) = 1 - 0.85

P(student not pass) = 0.15

probability that student passes = P(Student studies)(Student who pass) + P(Student not study)(student not pass)

probability that student passes = (0.85)(0.90) + (0.15)(0.11)

probability that student passes = 0.765 + 0.0165

probability that student passes = 0.7815

teleportation

step-by-step explanation: