Question

Studies show that about five women in seven (approximately 71.4%) who live to be 90 will develop breast cancer. Suppose that of those women who develop breast cancer, a test is negative 25% of the time. Also, suppose that in the general population of women, the test for breast cancer is negative about 45% of the time. Let B=women develops breast cancer, P=tests positive, and N=tests negative. Suppose one woman is selected at random. Round your answer to three decimal places. Given that a woman develops breast cancer, what is the probability that she tests positive. Find P(P|B) = 1-P(N|B). What is the probability that a woman develops breast cancer and tests positive. Find P(B AND P) = P(P|B)P(B). What is the probability that a woman does not develop breast cancer. Find P(B’) = 1-P(B). What is the probability that a woman tests positive for breast cancer. Find P(P)=1-P(N).

202

likes
1009 views

Answer to a math question Studies show that about five women in seven (approximately 71.4%) who live to be 90 will develop breast cancer. Suppose that of those women who develop breast cancer, a test is negative 25% of the time. Also, suppose that in the general population of women, the test for breast cancer is negative about 45% of the time. Let B=women develops breast cancer, P=tests positive, and N=tests negative. Suppose one woman is selected at random. Round your answer to three decimal places. Given that a woman develops breast cancer, what is the probability that she tests positive. Find P(P|B) = 1-P(N|B). What is the probability that a woman develops breast cancer and tests positive. Find P(B AND P) = P(P|B)P(B). What is the probability that a woman does not develop breast cancer. Find P(B’) = 1-P(B). What is the probability that a woman tests positive for breast cancer. Find P(P)=1-P(N).

Expert avatar
Fred
4.4
120 Answers
Let's define the events:

B : Woman develops breast cancer
P : Test result is positive
N : Test result is negative

Given probabilities:
P(B) = 5/7
P(N|B) = 0.25
P(N) = 0.45

1. Probability a woman who develops breast cancer tests positive: P(P|B) = 1 - P(N|B)
P(P|B) = 1 - P(N|B) = 1 - 0.25 = 0.75

2. Probability a woman develops breast cancer and tests positive: P(B and P) = P(P|B) \cdot P(B)
P(B and P) = P(P|B) \cdot P(B) = 0.75 \cdot 5/7 = 0.5357

3. Probability a woman does not develop breast cancer: P(B') = 1 - P(B)
P(B') = 1 - P(B) = 1 - 5/7 = 2/7 \approx 0.286

4. Probability a woman tests positive for breast cancer: P(P) = 1 - P(N)
P(P) = 1 - P(N) = 1 - 0.45 = 0.55

**Answer:**
1. P(P|B) = 0.75
2. P(B and P) = 0.5357
3. P(B') = 0.286
4. P(P) = 0.55

Frequently asked questions (FAQs)
What is the equation of the line passing through (2, 5) and (4, 11)?
+
What is the maximum value attained by the cosine function f(x) = cos x on the interval [-π/2, π/2]?
+
What is the scalar product of vector A with magnitude 3 and vector B with magnitude 4?
+
New questions in Mathematics
A circular park has a diameter of 150ft. A circular fence is to be placed on the edge of this park. Calculate the cost of fencing this park if the rate charged is $7 per foot. Use π = 3.14.
2x-y=5 x-y=4
X^2 = 25
By differentiating the function f(x)=(x³−6x)⁷ we will obtain
3x+5y=11 2x-3y=1
Perpetual annuities are a series of payments whose duration has no end. Explain how can we calculate them, if they have no end?
In a store, a person carries 14 kilos of rice and 28 kilos of flour. In what ratio are the kilos found? (Remember to simplify until you reach an irreducible fraction)
How many anagrams of the word SROMEC there that do not contain STROM, MOST, MOC or CEST as a subword? By subword is meant anything that is created by omitting some letters - for example, the word EMROSCT contains both MOC and MOST as subwords.
Solve the equation: sin(2x) = 0.35 Where 0° ≤ x ≤ 360°. Give your answers to 1 d.p.
A recurring sequence is one where elements repeat after completing one standard. If the sequence AB8C14D96AB8C1... is recurring its twentieth term is equal to: (A) B. (B) 8. (C) A. (D) 6. (E) D.
Convert 9/13 to a percent
Use a pattern to prove that (-2)-(-3)=1
Determine a general formula​ (or formulas) for the solution to the following equation.​ Then, determine the specific solutions​ (if any) on the interval [0,2π). cos30=0
How to convert 45 kg into grams
48 kg of 30% sulfuric acid in a mixture of 10% and 40% sulfuric acid arose. How many kilograms were each of the original solutions?
0<x<2π aralığındaki f(x)=x÷2 fonksiyonunun 0 < x < 4π için grafiğini çiziniz ve 0<x<2n için Fourier seri dönüşümünü gerçekleştiriniz.
To paint a 250 m wall, a number of workers were employed. If the wall were 30 m longer, 9 more workers would be needed. How many were employed at the beginning?
Determine the general solution of the equation y′+y=e−x .
3(x-4)=156
The car with an irresponsible driver starts to brake when it goes through a red light. When passing the traffic light, he does so at a speed of 115 kph in the right lane. Further ahead, 70 meters from the traffic light, a child is crossing the street and falls. If the effect of the car's brakes is equivalent to a deceleration of magnitude 5.7m/s². Is the child hit by the car or not? How far from the traffic light does the car stop?