A medical test will be positive for 0.05% of people and negative for everyone else. Suppose a hospital will test 4000 patients each day. Use an appropriate approximation to find the probability that 5 people test positive tomorrow. (5SF)

Note that we have a constant probability, fixed number of tests, independent patients and only two outcomes, so we can write a binomial distribution X~Bin(4000,0.0005) where X is the random variable representing the number of patients who test positive.Use a Poisson approximation with L=np=2, so P(X=5) = ~(e^(-2)2^5)/5! = 0.036089

Answered by John M. Maths tutor

2520 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

find the gradient of the tangent to the curve y=x^2 at the point (4,16)


find the integral of f'(x)=2x+5


Find exact solution to 2ln(2x+1) - 10 =0


i) Using implicit differentiation find dy/dx for x^2 + y^2 = 4 ii) At what points is the tangent to the curve parallel to the y axis iii) Given the line y=x+c only intersects the circle once find c given that c is positive.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences