Mathematics, 15.02.2021 20:10, eylinglez3ovm16v

Suppose a university is divided into three campuses: the Main campus, the Downtown campus, and the Bay Area campus. The Main campus has 60% of the university's students, the Downtown campus has 25%, and the Bay Area has the rest. At the Main campus, 12% of the students are statistics majors. At the Downtown campus, 4% of the students are statistics majors. Finally, at the Bay Area campus, 1% of the students are statistics majors. Required:
a. What proportion of students at the university are statistics majors?
b. Of all statistics majors at the university, what proportion are at the Main campus?

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answered: toddjordan1928

a) 0.0835 = 8.35% of students at the university are statistics majors

b) 0.8623 = 86.23% are at the Main campus

Step-by-step explanation:

Conditional Probability

We use the conditional probability formula to solve this question. It is

$P(B|A) = \frac{P(A \cap B)}{P(A)}$

In which

P(B|A) is the probability of event B happening, given that A happened.

$P(A \cap B)$ is the probability of both A and B happening.

P(A) is the probability of A happening.

This is used for item b.

a. What proportion of students at the university are statistics majors?

12% of 60%(At the main campus).

4% of 25%(Downtown campus).

The rest is 100 - 60 + 25) = 15%.

1% of 15%(Bay Area Campus). Si

p = 0.12*0.6 + 0.04*0.25 + 0.01*0.15 = 0.0835

0.0835 = 8.35% of students at the university are statistics majors.

b. Of all statistics majors at the university, what proportion are at the Main campus?

Using conditional probability to find the percentage.

Event A: Statistics majors, so P(A) = 0.0835

Event B: Main Campus

Intersection of A and B:

12% of 60%. So

$P(A \cap B) = 0.12*0.6 = 0.072$

Percentage:

$P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.072}{0.0835} = 0.8623$

0.8623 = 86.23% are at the Main campus

answered: Guest

Intersecting secant-tangent theorem states that if a tangent segment and a secant segment are drawn to a circle from an exterior point, then the square of the measure of the tangent segment is equal to the product of the measures of the secant segment and its external secant segment.so to break it down: 1. pq acts as the tangent and ps as the secant with an intersection at p.sr = 21rp = 3x + 3pq = 4x + 4following to equation: tangent squared = the two segments multiplied by each otherso (4x + 4) ^ 2 = (3x + 3) • (21) simplifies to 16x^2 - 31x - 47 = 0 or (16x - 47)(x + 1) x = -1 or x = 47/162. pq acts as the tangent and ps as the secant with an intersection at p (again! )sr = 16rp = xpq = 15(15) ^ 2 = 16 • x225 = 16xx = 225/163. the interesting chords are proportional to each other so a ratio is possible to set up: ap dp 10 3 + x = = —— = pc pb 8 xcross multiple to get 10x = (3 + x)(8)x = 12

answered: Guest

3-4

step-by-step explanation:

the answer is 3-4 because both 45 and 60 has a multiple of 15.

45/3=15

60/4=15

therefore the odds against selecting a red is 4-3