Question

Say you flip a coin seven times. What is the probability the number of heads will be even?

Answer 1

The probability the number of heads will be even is 0.4922.

Explanation:

Consider the provided information.

It is given that coin flip seven times.

Thus, the total number of possible outcomes are:
`2^7`

We want heads will be even.

Even numbers are 2, 4, 6.....

Thus, the possible case are: 2 heads, 4 heads or 6 heads.

The required probability is:

`(^7C_2+^7C_4+^7C_6)*(1)/(2^7)=\left((7!)/(2!5!)+(7!)/(4!3!)+(7!)/(6!1!)\right)(1)/(128)\approx 0.4922`

Hence, the probability the number of heads will be even is 0.4922.