Question

Flip a fair coin 5 times. What is the probability that at least one time the coin lands on heads?

Answer 1

When a fair coin is flipped once, there are 2 favorable outcomes i.e Head or Tail.

When a fair coin is flipped 5 times;

Total Favorable Outcomes= 2*2*2*2*2 =32

TO FIND:

The probability that at least one time the coin lands on heads

It means we can get 1,2,3,4 or all 5 heads.

The chance of getting a head in a fair coin flip is 1/2 i.e 50%.

The probability that at least one time the coin lands on heads = 31/32

Because there is one chance that all 5 times it can be a tail.

Rest all outcomes will definitely have at least one head.

All Outcomes Except Outcome Number 32.

Outcome Number	1st	2nd	3rd	4th	5th
1	H	H	H	H	H
2	H	H	H	H	T
3	H	H	H	T	H
4	H	H	H	T	T
5	H	H	T	H	H
6	H	H	T	H	T
7	H	H	T	T	H
8	H	H	T	T	T
9	H	T	H	H	H
10	H	T	H	H	T
11	H	T	H	T	H
12	H	T	H	T	T
13	H	T	T	H	H
14	H	T	T	H	T
15	H	T	T	T	H
16	H	T	T	T	T
17	T	H	H	H	H
18	T	H	H	H	T
19	T	H	H	T	H
20	T	H	H	T	T
21	T	H	T	H	H
22	T	H	T	H	T
23	T	H	T	T	H
24	T	H	T	T	T
25	T	T	H	H	H
26	T	T	H	H	T
27	T	T	H	T	H
28	T	T	H	T	T
29	T	T	T	H	H
30	T	T	T	H	T
31	T	T	T	T	H
32	T	T	T	T	T