Question:
Two fair coins are tossed together. What is the probability of getting at least one head?
Two fair coins are tossed together. What is the probability of getting at least one head?
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"At least one" is easiest via 1 minus P(none).
Updated On: Jul 8, 2026
- \(\dfrac{3}{4}\)
- \(\dfrac{1}{2}\)
- \(\dfrac{1}{4}\)
- \(1\)
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The Correct Option is A
Solution and Explanation
Step 1: Use the complement.
P(at least one head) \(= 1 - \)P(no head).
Step 2: Probability of no head.
No head means both tails: \[P(TT) = \dfrac{1}{2}\times\dfrac{1}{2} = \dfrac{1}{4}\] Step 3: Subtract.
\[1 - \dfrac{1}{4} = \boxed{\dfrac{3}{4}}\]
P(at least one head) \(= 1 - \)P(no head).
Step 2: Probability of no head.
No head means both tails: \[P(TT) = \dfrac{1}{2}\times\dfrac{1}{2} = \dfrac{1}{4}\] Step 3: Subtract.
\[1 - \dfrac{1}{4} = \boxed{\dfrac{3}{4}}\]
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