Josephine is taking a college course, and her professor bases the course grade on the average of two test taken in the semester. She wants to know what she needs to earn on the last test to maintain her grade. Rearrange the following questions for b, where C is the average of two test scores, a and b. (9th-grade Algebra 1)

1 3 5

step-by-step explanation:

i took the test: )

85.560%

step-by-step explanation:

conditional probability is defined as:

p(a|b) = p(a∩b) / p(b)

in other words, the probability that a occurs, given that b has occurred = the probability that both a and b occur / the probability that b occurs.

in this example:

p(turns 64 | turns 44) = p(turns 64 & turns 44) / p(turns 44).

if someone turns 64, they must have already turned 44, so:

p(turns 64 | turns 44) = p(turns 64) / p(turns 44)

on page 42, we see that of the original 100,000, 94944 turn 44, and 81234 turn 64.   therefore:

p(turns 64 | turns 44) = 81234 / 94944

p(turns 64 | turns 44) = 0.85560

answer: the answer is d