Question

1. A fair coin is flipped 400 times.

1. Calculate the mean and standard deviation for the number of heads.
2. Calculate the mean and standard deviation for the proportion of heads.
3. Calculate the approximate probability that the number of heads is at least 220.

Answer 1

From the given information,

n= 400

p= 0.5

Hence,

By using calculator,

The required correct answers are,

A. For number of heads,

Mean= 200

Sd= 10

B. For proportion of heads,

Mean= 0.5

Sd= 0.025

C.

P(X≥220)= 0.0228

Thank you.