Question

Giving medals to correct answer.
Joe is a fish thrower who throws fish into a chute at a processing plant. Joe misses the chute 20% of the time. Using the normal approximation with the continuity correction, which of these correctly represents the probability Joe will miss fewer than 80 times if he throws 500 fish?

P(X < 80) for N(100, 8.94)

P(X < 79.5) for N(100, 8.94)

P(X 80) for N(100, 8.94)

P(X < 80.5) for B(500, .2)

P(X < 80) for B(500, .2)

Answer 1

@Luigi0210

Answer 2

@kropot72

Answer 3

@ganeshie8

Answer 4

The mean number of misses is given by n * p = 500 * 0.2=100.
The standard deviation is given by:
\[\large S.D.=\sqrt{np(1-p)}=\sqrt{500\times0.2\times0.8}=8.94\]
To apply the continuity correction, we need to add 0.5 to 80 giving 80.5.
It appears, therefore , that none of the choices is correct.