A coin is tossed 5 times. Find the probability of getting (i) at least

1.	A coin is tossed 5 times. Find the probability of getting (i) at least4 heads, and (ii) at most 4 heads.
Answer» when a coin is tossed 5 times; number of possible outcomes = n(S) = 2^5 = 32. Now, more than 3 heads mean: (4 Heads + 1 Tail) and (5 Heads + 0 Tail). Now, (4 Heads + 1 Tail) can be obtained from [(5C4)*(1C1)] = 5 outcomes Also, (5 Heads + 0 Tail) can be obtained from [(5C5)] = 1 outcome 1)(1+5)/32=6/32=3/162)31/32

A coin is tossed 5 times. Find the probability of getting (i) at least4 heads, and (ii) at most 4 heads.

Answer»

when a coin is tossed 5 times; number of possible outcomes = n(S) = 2^5 = 32.

Now, more than 3 heads mean: (4 Heads + 1 Tail) and (5 Heads + 0 Tail).

Now, (4 Heads + 1 Tail) can be obtained from [(5C4)*(1C1)] = 5 outcomes

Also, (5 Heads + 0 Tail) can be obtained from [(5C5)] = 1 outcome

1)(1+5)/32=6/32=3/162)31/32