The random variable J has a Poisson distribution with mean 4. Find P(J>2)
P(J>2) = P(J=0)+P(J=1) [split it up]
P(X=t)= (V^t)/t!*e^V where V=4 in this case [use the formula]
P(J>2) = 4^0/0!*e^4 + 4^1/1!*e^4
=1/e^4 + 4/e^4 = 5e^-4 which is roughly 0.0916
NC
Related Maths A Level answers
All answers ▸Write (3 + 2√5)/(7 + 3√5) in the form a + b√5
Why is the inverse of a gradient -1/x?
Given that sin(x)^2 + cos(x)^2 = 1, show that sec(x)^2 - tan(x)^2 = 1 (2 marks). Hence solve for x: tan(x)^2 + cos(x) = 1, x ≠ (2n + 1)π and -2π < x =< 2π(3 marks)
Use the quotient rule to differentiate: ln(3x)/(e^4x) with respect to x.