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A fair coin is tossed five times. What is the probability of getting 'heads' at the most once out of the five tosses?

Probability of 0 Heads/5: TTTTT = \((1/2)^5 \)(Only one way to get 5 Tails)
probability of 1 Heads/5: HTTTT = \((1/2)^5*\frac{5!}{4!} \) (As number of ways to arrange 5 results with 4 similar results = 5!/4!)

Hence total probability: \((1/2)^5 + (1/2)^*\frac{5!}{4!} = 3/16\)
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Step 1: Total Outcomes
A fair coin has 2 outcomes per toss. For 5 tosses:
Total outcomes = 2^5 = 32

Step 2: Probability of No Heads
All tails (TTTTT) = 1 outcome.
P(no heads) = 1/32

Step 3: Probability of Exactly 1 Head
Exactly 1 head can occur in 5 ways.
P(exactly 1 head) = 5/32

Step 4: Probability of At Most 1 Head
At most 1 head means no heads or exactly 1 head.
P(at most 1 head) = P(no heads) + P(exactly 1 head)
P(at most 1 head) = 1/32 + 5/32 = 6/32 = 3/16
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atmost one head in 5 toss => no head + one head

No head = TTTTT = 1/2^5
One head = 5C1 * 1/2^5

hence total = 6/2^5 = 3/16 (Option C)
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