1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Sophie [7]
3 years ago
10

Christine has always been weak in mathematics. Based on her performance prior to the final exam in Calculus, there is a 51% chan

ce that she will fail the course if she does not have someone to coach her. With a coach, her probability of failing decreases to 21%. There is only a 61% chance that she will find someone at such short notice.
a. What is the probability that Christine fails the course? (Round your answer to 4 decimal places.)

b. Christine ends up failing the course. What is the probability that she had found someone to help? (Round your answer to 4 decimal places.)
Mathematics
1 answer:
Charra [1.4K]3 years ago
4 0

Answer:

a) 0.3270 = 32.70% probability that Christine fails the course

b) 0.3917 = 39.17% probability that she had found someone to help

Step-by-step explanation:

We have these following probabilities:

61% probability that Christine find a coach.

100 - 61 = 39% probability that Christine does not find a coach.

With a coach, a 21% probability of failing.

Without a coach, a 51% probability of failing.

a. What is the probability that Christine fails the course?

21% of 61%(finds a tutor) plus 51% of 39%(does not find a tutor). So

P = 0.21*0.61 + 0.51*0.39 = 0.327.

0.327 = 32.7% probability that Christine fails the course

b. Christine ends up failing the course. What is the probability that she had found someone to help?

This can be formulated by the Bayes formula:

P(B|A) = \frac{P(B)*P(A|B)}{P(A)}

In which P(B|A) is the probability of B happening given that A happened and P(A|B) is the probability of A happening given that B happened.

In this question.

P(B|A) is the probability of finding a tutor given that she failed.

P(B) is the probability of finding a tutor. So P(B) = 0.61.

P(A|B) is the probability of failing when finding a tutor. So P(A|B) = 0.21

P(A) is the probability of failing. So P(A) = 0.327.

So

P(B|A) = \frac{P(B)*P(A|B)}{P(A)} = \frac{0.61*0.21}{0.327} = 0.3917

0.3917 = 39.17% probability that she had found someone to help

You might be interested in
The expression y2 – 10y + 24 has a factor of y – 4. What is another factor of y2 – 10y + 24? y – 20 y – 14 y – 8 y – 6
aniked [119]
Just for future reference always put ^ for exponents. The answer is y-6 though. 
(y-4)(y-6) create that trinomial. You can prove that by using the FOIL algorithm 
7 0
3 years ago
Read 2 more answers
Point Y is in the interior of ∠XWZ. Given that WX→ and WZ→ are are opposite rays, and m∠XWY=4(m∠YWZ) is m∠YWZ?.
EleoNora [17]

Answer:

m∠YWZ=36°

Step-by-step explanation:

Opposite rays are two rays that both start from a common point and go off in exactly opposite directions. Because of this the two rays (WX and WZ) form a single straight line through the common endpoint W.

If rays WX and WZ are opposite, then angle XWZ is straight angle. A straight angle always has the measure of 180°.

Point Y is in the interior of ∠XWZ, then angles XWY and EWZ are supplementary angles (together form straight angle XWZ). Supplementary angles always add up to 180°, then

m∠XWY+m∠YWZ=180°

You are given that

m∠XWY=4(m∠YWZ).

Substitute it into the previous equality:

4(m∠YWZ)+m\angle YWZ=180°

5(m∠YWZ)=180°

m∠YWZ=36°

5 0
3 years ago
If a line with a slope of -2 crosses the y-axis at (0,3) what is the equation of the line
Ghella [55]
Hello!

The equation can be written as seen below. You only need a y-intercept and slope to write the equation.

y=-2x+3                             (it intercepts at a y-value of 3).

I hope this helps!
5 0
3 years ago
I need help please asap
Elenna [48]

Answer:

22. C to D

23. Sam's height

Step-by-step explanation:

Acronym: King Henry Died Unusually Drinking Chocolate Milk

                i         e        e       n                e             e                i

                l         c         c       i                 c             n                l

                o        t         a        t                 i              t                l

                          o                                                    i                i

22. 4 km < 4.15 km

23. 1.16 m > 0.98 m

8 0
3 years ago
35 to 77 simplified is
polet [3.4K]

Answer:

5/11

Step-by-step explanation:

35 to 77 simplified is 5/11

35 ÷ 7

---------

77 ÷ 7

Therefore, 35/77 simplified to lowest terms is 5/11.

Hope that helps

And if wrong sorry

5 0
3 years ago
Other questions:
  • Billy Bob and Charline are riding the Ferris wheel at the county fair. Billy Bob exits the ride when he becomes sick
    9·1 answer
  • The expression 3/4×1/2 represents a fraction of a circle that is shaded. Which diagram shows the correct shading?
    15·2 answers
  • What is an equation of the line that contains the point (3 -1) and is perpendicular to the line whose equation is y=-3x+2?
    11·1 answer
  • Solve for n; 1.2n + 0.68 = 5
    8·2 answers
  • The height of a building is 1734 ft. How long would it take an object to fall to the ground from the​ top? Use the formula s equ
    13·1 answer
  • Alex wrote 103.903 in expanded form as 100+3x1+9x1/100+3x1/1000. Explain his mistake. Then tell how to correct it.
    7·1 answer
  • A number increased by 24 is 112. what is the number
    7·1 answer
  • My twin and I constantly argue about who is the elder. He claims that just because he was born first, he is older than I am. I r
    7·1 answer
  • NEED HELP ASAP! Which number is between -0.49 and 0.01 on a number line?
    9·1 answer
  • Simplify (-1 1/2) ÷ 3/4 x -2/3
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!